1
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Lohitaksha K, Kumari D, Shukla M, Byagari L, Ashireddygari VR, Tammineni P, Reddanna P, Gorla M. Eicosanoid signaling in neuroinflammation associated with Alzheimer's disease. Eur J Pharmacol 2024; 976:176694. [PMID: 38821162 DOI: 10.1016/j.ejphar.2024.176694] [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: 02/29/2024] [Revised: 05/28/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
Alzheimer's disease (AD) is a prevalent neurodegenerative condition affecting a substantial portion of the global population. It is marked by a complex interplay of factors, including the accumulation of amyloid plaques and tau tangles within the brain, leading to neuroinflammation and neuronal damage. Recent studies have underscored the role of free lipids and their derivatives in the initiation and progression of AD. Eicosanoids, metabolites of polyunsaturated fatty acids like arachidonic acid (AA), emerge as key players in this scenario. Remarkably, eicosanoids can either promote or inhibit the development of AD, and this multifaceted role is determined by how eicosanoid signaling influences the immune responses within the brain. However, the precise molecular mechanisms dictating the dual role of eicosanoids in AD remain elusive. In this comprehensive review, we explore the intricate involvement of eicosanoids in neuronal function and dysfunction. Furthermore, we assess the therapeutic potential of targeting eicosanoid signaling pathways as a viable strategy for mitigating or halting the progression of AD.
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Affiliation(s)
| | - Deepika Kumari
- Department of Biochemistry, Central University of Rajasthan, Bandarsindri, Ajmer, Rajasthan, India
| | - Manas Shukla
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Lavanya Byagari
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | | | - Prasad Tammineni
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Pallu Reddanna
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India; Brane Enterprises Private Limited, Hyderabad, India.
| | - Madhavi Gorla
- National Institute of Animal Biotechnology, Hyderabad, India.
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2
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Liu S, Anderson PJ, Rajagopal S, Lefkowitz RJ, Rockman HA. G Protein-Coupled Receptors: A Century of Research and Discovery. Circ Res 2024; 135:174-197. [PMID: 38900852 PMCID: PMC11192237 DOI: 10.1161/circresaha.124.323067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
GPCRs (G protein-coupled receptors), also known as 7 transmembrane domain receptors, are the largest receptor family in the human genome, with ≈800 members. GPCRs regulate nearly every aspect of human physiology and disease, thus serving as important drug targets in cardiovascular disease. Sharing a conserved structure comprised of 7 transmembrane α-helices, GPCRs couple to heterotrimeric G-proteins, GPCR kinases, and β-arrestins, promoting downstream signaling through second messengers and other intracellular signaling pathways. GPCR drug development has led to important cardiovascular therapies, such as antagonists of β-adrenergic and angiotensin II receptors for heart failure and hypertension, and agonists of the glucagon-like peptide-1 receptor for reducing adverse cardiovascular events and other emerging indications. There continues to be a major interest in GPCR drug development in cardiovascular and cardiometabolic disease, driven by advances in GPCR mechanistic studies and structure-based drug design. This review recounts the rich history of GPCR research, including the current state of clinically used GPCR drugs, and highlights newly discovered aspects of GPCR biology and promising directions for future investigation. As additional mechanisms for regulating GPCR signaling are uncovered, new strategies for targeting these ubiquitous receptors hold tremendous promise for the field of cardiovascular medicine.
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Affiliation(s)
- Samuel Liu
- Department of Medicine, Duke University Medical
Center
| | - Preston J. Anderson
- Cell and Molecular Biology (CMB), Duke University, Durham,
NC, 27710, USA
- Duke Medical Scientist Training Program, Duke University,
Durham, NC, 27710, USA
| | - Sudarshan Rajagopal
- Department of Medicine, Duke University Medical
Center
- Cell and Molecular Biology (CMB), Duke University, Durham,
NC, 27710, USA
- Deparment of Biochemistry Duke University, Durham, NC,
27710, USA
| | - Robert J. Lefkowitz
- Department of Medicine, Duke University Medical
Center
- Deparment of Biochemistry Duke University, Durham, NC,
27710, USA
- Howard Hughes Medical Institute, Duke University Medical
Center, Durham, North Carolina 27710, USA
| | - Howard A. Rockman
- Department of Medicine, Duke University Medical
Center
- Cell and Molecular Biology (CMB), Duke University, Durham,
NC, 27710, USA
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3
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Thotamune W, Ubeysinghe S, Rajarathna C, Kankanamge D, Olupothage K, Chandu A, Copits BA, Karunarathne A. AGS3-based optogenetic GDI induces GPCR-independent Gβγ signaling and macrophage migration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.04.597473. [PMID: 38895415 PMCID: PMC11185739 DOI: 10.1101/2024.06.04.597473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
G protein-coupled receptors (GPCRs) are efficient Guanine nucleotide exchange factors (GEFs) and exchange GDP to GTP on the Gα subunit of G protein heterotrimers in response to various extracellular stimuli, including neurotransmitters and light. GPCRs primarily broadcast signals through activated G proteins, GαGTP, and free Gβγ, and are major disease drivers. Evidence shows that the ambient low threshold signaling required for cells is likely supplemented by signaling regulators such as non-GPCR GEFs and Guanine nucleotide Dissociation Inhibitors (GDIs). Activators of G protein Signaling 3 (AGS3) are recognized as a GDI involved in multiple health and disease-related processes. Nevertheless, understanding of AGS3 is limited, and no significant information is available on its structure-function relationship or signaling regulation in living cells. Here, we employed in silico structure-guided engineering of a novel optogenetic GDI, based on the AGS3's G protein regulatory (GPR) motif, to understand its GDI activity and induce standalone Gβγ signaling in living cells on optical command. Our results demonstrate that plasma membrane recruitment of OptoGDI efficiently releases Gβγ, and its subcellular targeting generated localized PIP3 and triggered macrophage migration. Therefore, we propose OptoGDI as a powerful tool for optically dissecting GDI-mediated signaling pathways and triggering GPCR-independent Gβγ signaling in cells and in vivo.
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Affiliation(s)
- Waruna Thotamune
- Department of Chemistry, Saint Louis University, Saint Louis, MO 63103, USA
- Institute for Drug and Biotherapeutic Innovation, Saint Louis University, Saint Louis, MO 63103, USA
| | - Sithurandi Ubeysinghe
- Department of Chemistry, Saint Louis University, Saint Louis, MO 63103, USA
- Institute for Drug and Biotherapeutic Innovation, Saint Louis University, Saint Louis, MO 63103, USA
| | - Chathuri Rajarathna
- Department of Chemistry, Saint Louis University, Saint Louis, MO 63103, USA
- Institute for Drug and Biotherapeutic Innovation, Saint Louis University, Saint Louis, MO 63103, USA
| | - Dinesh Kankanamge
- Washington University Pain Center, Department of Anesthesiology, Washington University School of Medicine; St. Louis, MO 63110 USA
| | - Koshala Olupothage
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Aditya Chandu
- Department of Chemistry, Saint Louis University, Saint Louis, MO 63103, USA
| | - Bryan A. Copits
- Washington University Pain Center, Department of Anesthesiology, Washington University School of Medicine; St. Louis, MO 63110 USA
| | - Ajith Karunarathne
- Department of Chemistry, Saint Louis University, Saint Louis, MO 63103, USA
- Institute for Drug and Biotherapeutic Innovation, Saint Louis University, Saint Louis, MO 63103, USA
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4
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Lichner Z, Ding M, Khare T, Dan Q, Benitez R, Praszner M, Song X, Saleeb R, Hinz B, Pei Y, Szászi K, Kapus A. Myocardin-Related Transcription Factor Mediates Epithelial Fibrogenesis in Polycystic Kidney Disease. Cells 2024; 13:984. [PMID: 38891116 PMCID: PMC11172104 DOI: 10.3390/cells13110984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/21/2024] [Accepted: 05/27/2024] [Indexed: 06/21/2024] Open
Abstract
Polycystic kidney disease (PKD) is characterized by extensive cyst formation and progressive fibrosis. However, the molecular mechanisms whereby the loss/loss-of-function of Polycystin 1 or 2 (PC1/2) provokes fibrosis are largely unknown. The small GTPase RhoA has been recently implicated in cystogenesis, and we identified the RhoA/cytoskeleton/myocardin-related transcription factor (MRTF) pathway as an emerging mediator of epithelium-induced fibrogenesis. Therefore, we hypothesized that MRTF is activated by PC1/2 loss and plays a critical role in the fibrogenic reprogramming of the epithelium. The loss of PC1 or PC2, induced by siRNA in vitro, activated RhoA and caused cytoskeletal remodeling and robust nuclear MRTF translocation and overexpression. These phenomena were also manifested in PKD1 (RC/RC) and PKD2 (WS25/-) mice, with MRTF translocation and overexpression occurring predominantly in dilated tubules and the cyst-lining epithelium, respectively. In epithelial cells, a large cohort of PC1/PC2 downregulation-induced genes was MRTF-dependent, including cytoskeletal, integrin-related, and matricellular/fibrogenic proteins. Epithelial MRTF was necessary for the paracrine priming of the fibroblast-myofibroblast transition. Thus, MRTF acts as a prime inducer of epithelial fibrogenesis in PKD. We propose that RhoA is a common upstream inducer of both histological hallmarks of PKD: cystogenesis and fibrosis.
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Affiliation(s)
- Zsuzsanna Lichner
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
| | - Mei Ding
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
| | - Tarang Khare
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
- Enrich Bioscience, Toronto, ON M5B 1T8, Canada
| | - Qinghong Dan
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
| | - Raquel Benitez
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
| | - Mercédesz Praszner
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
| | - Xuewen Song
- Division of Nephrology, University Health Network, Toronto, ON M5G 2C4, Canada
| | - Rola Saleeb
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
- Department of Laboratory Medicine and Pathobiology, Temerty School of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Boris Hinz
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada
| | - York Pei
- Division of Nephrology, University Health Network, Toronto, ON M5G 2C4, Canada
| | - Katalin Szászi
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
- Department of Laboratory Medicine and Pathobiology, Temerty School of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Surgery, University of Toronto, Toronto, ON M5T 1P5, Canada
| | - András Kapus
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada; (Z.L.); (T.K.); (R.S.); (K.S.)
- Department of Surgery, University of Toronto, Toronto, ON M5T 1P5, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
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5
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Dates AN, Jones DTD, Smith JS, Skiba MA, Rich MF, Burruss MM, Kruse AC, Blacklow SC. Heterogeneity of tethered agonist signaling in adhesion G protein-coupled receptors. Cell Chem Biol 2024:S2451-9456(24)00120-X. [PMID: 38608683 DOI: 10.1016/j.chembiol.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/25/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024]
Abstract
Adhesion G protein-coupled receptor (aGPCR) signaling influences development and homeostasis in a wide range of tissues. In the current model for aGPCR signaling, ligand binding liberates a conserved sequence that acts as an intramolecular, tethered agonist (TA), yet this model has not been evaluated systematically for all aGPCRs. Here, we assessed the TA-dependent activities of all 33 aGPCRs in a suite of transcriptional reporter, G protein activation, and β-arrestin recruitment assays using a new fusion protein platform. Strikingly, only ∼50% of aGPCRs exhibited robust TA-dependent activation, and unlike other GPCR families, aGPCRs showed a notable preference for G12/13 signaling. AlphaFold2 predictions assessing TA engagement in the predicted intramolecular binding pocket aligned with the TA dependence of the cellular responses. This dataset provides a comprehensive resource to inform the investigation of all human aGPCRs and for targeting aGPCRs therapeutically.
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Affiliation(s)
- Andrew N Dates
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel T D Jones
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Jeffrey S Smith
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Dermatology, Brigham and Women's Hospital, 221 Longwood Avenue, Boston, MA 02115, USA
| | - Meredith A Skiba
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Maria F Rich
- University of Cincinnati School of Medicine, Department of Molecular Genetics, Biochemistry, and Microbiology, Cincinnati, OH 45267, USA
| | - Maggie M Burruss
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew C Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA 02215, USA.
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6
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Franco R, Garrigós C, Lillo J. The Olfactory Trail of Neurodegenerative Diseases. Cells 2024; 13:615. [PMID: 38607054 PMCID: PMC11012126 DOI: 10.3390/cells13070615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 03/19/2024] [Accepted: 03/27/2024] [Indexed: 04/13/2024] Open
Abstract
Alterations in olfactory functions are proposed as possible early biomarkers of neurodegenerative diseases. Parkinson's and Alzheimer's diseases manifest olfactory dysfunction as a symptom, which is worth mentioning. The alterations do not occur in all patients, but they can serve to rule out neurodegenerative pathologies that are not associated with small deficits. Several prevalent neurodegenerative conditions, including impaired smell, arise in the early stages of Parkinson's and Alzheimer's diseases, presenting an attractive prospect as a snitch for early diagnosis. This review covers the current knowledge on the link between olfactory deficits and Parkinson's and Alzheimer's diseases. The review also covers the emergence of olfactory receptors as actors in the pathophysiology of these diseases. Olfactory receptors are not exclusively expressed in olfactory sensory neurons. Olfactory receptors are widespread in the human body; they are expressed, among others, in the testicles, lungs, intestines, kidneys, skin, heart, and blood cells. Although information on these ectopically expressed olfactory receptors is limited, they appear to be involved in cell recognition, migration, proliferation, wound healing, apoptosis, and exocytosis. Regarding expression in non-chemosensory regions of the central nervous system (CNS), future research should address the role, in both the glia and neurons, of olfactory receptors. Here, we review the limited but relevant information on the altered expression of olfactory receptor genes in Parkinson's and Alzheimer's diseases. By unraveling how olfactory receptor activation is involved in neurodegeneration and identifying links between olfactory structures and neuronal death, valuable information could be gained for early diagnosis and intervention strategies in neurodegenerative diseases.
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Affiliation(s)
- Rafael Franco
- Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain;
- CiberNed, Network Center for Neurodegenerative Diseases, National Spanish Health Institute Carlos III, 28029 Madrid, Spain
- School of Chemistry, University of Barcelona, 08028 Barcelona, Spain
| | - Claudia Garrigós
- Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain;
| | - Jaume Lillo
- Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain;
- CiberNed, Network Center for Neurodegenerative Diseases, National Spanish Health Institute Carlos III, 28029 Madrid, Spain
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7
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Haspel N, Jang H, Nussinov R. Allosteric Activation of RhoA Complexed with p115-RhoGEF Deciphered by Conformational Dynamics. J Chem Inf Model 2024; 64:862-873. [PMID: 38215280 DOI: 10.1021/acs.jcim.3c01412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2024]
Abstract
The Ras homologue family member A (RhoA) is a member of the Rho family, a subgroup of the Ras superfamily. RhoA interacts with the 115 kDa guanine nucleotide exchange factor (p115-RhoGEF), which assists in activation and binding with downstream effectors. Here, we use molecular dynamics (MD) simulations and essential dynamics analysis of the inactive RhoA-GDP and active RhoA-GTP, when bound to p115-RhoGEF to decipher the mechanism of RhoA activation at the structural level. We observe that inactive RhoA-GDP maintains its position near the catalytic site on the Dbl homology (DH) domain of p115-RhoGEF through the interaction of its Switch I region with the DH domain. We further show that the active RhoA-GTP is engaged in more interactions with the p115-RhoGEF membrane-bound Pleckstrin homology (PH) domain as compared to RhoA-GDP. We hypothesize that the role of the interactions between the active RhoA-GTP and the PH domain is to help release it from the DH domain upon activation. Our results support this premise, and our simulations uncover the beginning of this process and provide structural details. They also point to allosteric communication pathways that take part in RhoA activation to promote and strengthen the interaction between the active RhoA-GTP and the PH domain. Allosteric regulation also occurs among other members of the Rho superfamily. Collectively, we suggest that in the activation process, the role of the RhoA-GTP interaction with the PH domain is to release RhoA-GTP from the DH domain after activation, making it available to downstream effectors.
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Affiliation(s)
- Nurit Haspel
- Department of Computer Science, University of Massachusetts Boston, Boston, Massachusetts 02125, United States
| | - Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Cancer Innovation Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Cancer Innovation Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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Chaim OM, Miki S, Prager BC, Ma J, Jeong AY, Lara J, Tran NK, Smith JM, Rich JN, Gutkind JS, Miyamoto S, Furnari FB, Brown JH. Gα12 signaling regulates transcriptional and phenotypic responses that promote glioblastoma tumor invasion. Sci Rep 2023; 13:22412. [PMID: 38104152 PMCID: PMC10725435 DOI: 10.1038/s41598-023-49164-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 12/05/2023] [Indexed: 12/19/2023] Open
Abstract
In silico interrogation of glioblastoma (GBM) in The Cancer Genome Atlas (TCGA) revealed upregulation of GNA12 (Gα12), encoding the alpha subunit of the heterotrimeric G-protein G12, concomitant with overexpression of multiple G-protein coupled receptors (GPCRs) that signal through Gα12. Glioma stem cell lines from patient-derived xenografts also showed elevated levels of Gα12. Knockdown (KD) of Gα12 was carried out in two different human GBM stem cell (GSC) lines. Tumors generated in vivo by orthotopic injection of Gα12KD GSC cells showed reduced invasiveness, without apparent changes in tumor size or survival relative to control GSC tumor-bearing mice. Transcriptional profiling of GSC-23 cell tumors revealed significant differences between WT and Gα12KD tumors including reduced expression of genes associated with the extracellular matrix, as well as decreased expression of stem cell genes and increased expression of several proneural genes. Thrombospondin-1 (THBS1), one of the genes most repressed by Gα12 knockdown, was shown to be required for Gα12-mediated cell migration in vitro and for in vivo tumor invasion. Chemogenetic activation of GSC-23 cells harboring a Gα12-coupled DREADD also increased THBS1 expression and in vitro invasion. Collectively, our findings implicate Gα12 signaling in regulation of transcriptional reprogramming that promotes invasiveness, highlighting this as a potential signaling node for therapeutic intervention.
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Affiliation(s)
- Olga Meiri Chaim
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA.
- Department of Cell Biology, Federal University of Paraná, Curitiba, Brazil.
| | - Shunichiro Miki
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
- Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, CA, USA
| | - Briana C Prager
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Jianhui Ma
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
- Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, CA, USA
| | - Anthony Y Jeong
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
| | - Jacqueline Lara
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
| | - Nancy K Tran
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
| | - Jeffrey M Smith
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
| | - Jeremy N Rich
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - J Silvio Gutkind
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
- Moores Cancer Center, University of California at San Diego, La Jolla, CA, USA
| | - Shigeki Miyamoto
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
| | - Frank B Furnari
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
- Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, CA, USA
| | - Joan Heller Brown
- Department of Pharmacology, University of California San Diego, Biomedical Sciences Building, 9500 Gilman Drive #0636, La Jolla, CA, 92093-0636, USA
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9
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Kleinjan ML, Mao DY, Naiche LA, Joshi JC, Gupta A, Jesse JJ, Shaye DD, Mehta D, Kitajewski J. CLIC4 Regulates Endothelial Barrier Control by Mediating PAR1 Signaling via RhoA. Arterioscler Thromb Vasc Biol 2023; 43:1441-1454. [PMID: 37317855 PMCID: PMC10527476 DOI: 10.1161/atvbaha.123.319206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 05/30/2023] [Indexed: 06/16/2023]
Abstract
BACKGROUND Endothelial CLICs (chloride intracellular channel proteins) CLIC1 and CLIC4 are required for the GPCRs (G-protein-coupled receptors) S1PR1 (sphingosine-1-phosphate receptor 1) and S1PR3 to activate the small GTPases Rac1 (Ras-related C3 botulinum toxin substrate 1) and RhoA (Ras homolog family member A). To determine whether CLIC1 and CLIC4 function in additional endothelial GPCR pathways, we evaluated CLIC function in thrombin signaling via the thrombin-regulated PAR1 (protease-activated receptor 1) and downstream effector RhoA. METHODS We assessed the ability of CLIC1 and CLIC4 to relocalize to cell membranes in response to thrombin in human umbilical vein endothelial cells (HUVEC). We examined CLIC1 and CLIC4 function in HUVEC by knocking down expression of each CLIC protein and compared thrombin-mediated RhoA or Rac1 activation, ERM (ezrin/radixin/moesin) phosphorylation, and endothelial barrier modulation in control and CLIC knockdown HUVEC. We generated a conditional murine allele of Clic4 and examined PAR1-mediated lung microvascular permeability and retinal angiogenesis in mice with endothelial-specific loss of Clic4. RESULTS Thrombin promoted relocalization of CLIC4, but not CLIC1, to HUVEC membranes. Knockdown of CLIC4 in HUVEC reduced thrombin-mediated RhoA activation, ERM phosphorylation, and endothelial barrier disruption. Knockdown of CLIC1 did not reduce thrombin-mediated RhoA activity but prolonged the RhoA and endothelial barrier response to thrombin. Endothelial-specific deletion of Clic4 in mice reduced lung edema and microvascular permeability induced by PAR1 activating peptide. CONCLUSIONS CLIC4 is a critical effector of endothelial PAR1 signaling and is required to regulate RhoA-mediated endothelial barrier disruption in cultured endothelial cells and murine lung endothelium. CLIC1 was not critical for thrombin-mediated barrier disruption but contributed to the barrier recovery phase after thrombin treatment.
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Affiliation(s)
- Matthew L. Kleinjan
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - De Yu Mao
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - L. A. Naiche
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Jagdish C. Joshi
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL, USA
| | - Ahana Gupta
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Jordan J. Jesse
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Daniel D. Shaye
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Dolly Mehta
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL, USA
| | - Jan Kitajewski
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
- University of Illinois Cancer Center, Chicago, IL, USA
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10
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Ramirez-Velez I, Belardi B. Storming the gate: New approaches for targeting the dynamic tight junction for improved drug delivery. Adv Drug Deliv Rev 2023; 199:114905. [PMID: 37271282 PMCID: PMC10999255 DOI: 10.1016/j.addr.2023.114905] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/20/2023] [Accepted: 05/29/2023] [Indexed: 06/06/2023]
Abstract
As biologics used in the clinic outpace the number of new small molecule drugs, an important challenge for their efficacy and widespread use has emerged, namely tissue penetrance. Macromolecular drugs - bulky, high-molecular weight, hydrophilic agents - exhibit low permeability across biological barriers. Epithelial and endothelial layers, for example within the gastrointestinal tract or at the blood-brain barrier, present the most significant obstacle to drug transport. Within epithelium, two subcellular structures are responsible for limiting absorption: cell membranes and intercellular tight junctions. Previously considered impenetrable to macromolecular drugs, tight junctions control paracellular flux and dictate drug transport between cells. Recent work, however, has shown tight junctions to be dynamic, anisotropic structures that can be targeted for delivery. This review aims to summarize new approaches for targeting tight junctions, both directly and indirectly, and to highlight how manipulation of tight junction interactions may help usher in a new era of precision drug delivery.
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Affiliation(s)
- Isabela Ramirez-Velez
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX 78712, United States
| | - Brian Belardi
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX 78712, United States.
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11
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Yeo RW, Zhou OY, Zhong BL, Sun ED, Navarro Negredo P, Nair S, Sharmin M, Ruetz TJ, Wilson M, Kundaje A, Dunn AR, Brunet A. Chromatin accessibility dynamics of neurogenic niche cells reveal defects in neural stem cell adhesion and migration during aging. NATURE AGING 2023; 3:866-893. [PMID: 37443352 PMCID: PMC10353944 DOI: 10.1038/s43587-023-00449-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 06/02/2023] [Indexed: 07/15/2023]
Abstract
The regenerative potential of brain stem cell niches deteriorates during aging. Yet the mechanisms underlying this decline are largely unknown. Here we characterize genome-wide chromatin accessibility of neurogenic niche cells in vivo during aging. Interestingly, chromatin accessibility at adhesion and migration genes decreases with age in quiescent neural stem cells (NSCs) but increases with age in activated (proliferative) NSCs. Quiescent and activated NSCs exhibit opposing adhesion behaviors during aging: quiescent NSCs become less adhesive, whereas activated NSCs become more adhesive. Old activated NSCs also show decreased migration in vitro and diminished mobilization out of the niche for neurogenesis in vivo. Using tension sensors, we find that aging increases force-producing adhesions in activated NSCs. Inhibiting the cytoskeletal-regulating kinase ROCK reduces these adhesions, restores migration in old activated NSCs in vitro, and boosts neurogenesis in vivo. These results have implications for restoring the migratory potential of NSCs and for improving neurogenesis in the aged brain.
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Affiliation(s)
- Robin W Yeo
- Department of Genetics, Stanford University, Stanford, CA, USA
| | - Olivia Y Zhou
- Department of Genetics, Stanford University, Stanford, CA, USA
- Stanford Biophysics Program, Stanford University, Stanford, CA, USA
- Stanford Medical Scientist Training Program, Stanford University, Stanford, CA, USA
| | - Brian L Zhong
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Eric D Sun
- Department of Genetics, Stanford University, Stanford, CA, USA
- Biomedical Informatics Graduate Program, Stanford University, Stanford, CA, USA
| | | | - Surag Nair
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | - Mahfuza Sharmin
- Department of Genetics, Stanford University, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | - Tyson J Ruetz
- Department of Genetics, Stanford University, Stanford, CA, USA
| | - Mikaela Wilson
- Department of Genetics, Stanford University, Stanford, CA, USA
| | - Anshul Kundaje
- Department of Genetics, Stanford University, Stanford, CA, USA
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA, USA.
- Glenn Laboratories for the Biology of Aging, Stanford University, Stanford, CA, USA.
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA.
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12
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Franco R, Navarro G, Martínez-Pinilla E. The adenosine A 2A receptor in the basal ganglia: Expression, heteromerization, functional selectivity and signalling. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 170:49-71. [PMID: 37741696 DOI: 10.1016/bs.irn.2023.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/25/2023]
Abstract
Adenosine is a neuroregulatory nucleoside that acts through four G protein-coupled receptors (GPCRs), A1, A2A, A2B and A3, which are widely expressed in cells of the nervous system. The A2A receptor (A2AR), the GPCR with the highest expression in the striatum, has a similar role to that of receptors for dopamine, one of the main neurotransmitters. Neuronal and glial A2ARs participate in the modulation of dopaminergic transmission and act in almost any action in which the basal ganglia is involved. This chapter revisits the expression of the A2AR in the basal ganglia in health and disease, and describes the diversity of signalling depending on whether the receptors are expressed as monomer or as heteromer. The A2AR can interact with other receptors as adenosine A1, dopamine D2, or cannabinoid CB1 to form heteromers with relevant functions in the basal ganglia. Heteromerization, with these and other GPCRs, provides diversity to A2AR-mediated signalling and to the modulation of neurotransmission. Thus, selective A2AR antagonists have neuroprotective potential acting directly on neurons, but also through modulation of glial cell activation, for example, by decreasing neuroinflammatory events that accompany neurodegenerative diseases. In fact, A2AR antagonists are safe and their potential in the therapy of Parkinson's disease has already led to the approval of one of them, istradefylline, in Japan and United States. The receptor also has a key role in reward circuits and, again, heteromers with dopamine receptors, but also with cannabinoid CB1 receptors, participate in the events triggered by drugs of abuse.
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Affiliation(s)
- Rafael Franco
- Molecular Neurobiology laboratory, Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, Universitat de Barcelona, Barcelona, Spain; CiberNed, Network Center for Neurodegenerative diseases, National Spanish Health Institute Carlos III, Madrid, Spain; School of Chemistry, Universitat de Barcelona, Barcelona, Spain.
| | - Gemma Navarro
- CiberNed, Network Center for Neurodegenerative diseases, National Spanish Health Institute Carlos III, Madrid, Spain; Department of Biochemistry and Physiology, School of Pharmacy and Food Science Universitat de Barcelona, Barcelona, Spain; Institute of Neurosciences, Universitat de Barcelona, Barcelona, Spain
| | - Eva Martínez-Pinilla
- Department of Morphology and Cell Biology, Faculty of Medicine, University of Oviedo, Asturias, Spain; Instituto de Neurociencias del Principado de Asturias (INEUROPA), Asturias, Spain; Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
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13
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Cekanaviciute E, Tran D, Nguyen H, Lopez Macha A, Pariset E, Langley S, Babbi G, Malkani S, Penninckx S, Schisler JC, Nguyen T, Karpen GH, Costes SV. Mouse genomic associations with in vitro sensitivity to simulated space radiation. LIFE SCIENCES IN SPACE RESEARCH 2023; 36:47-58. [PMID: 36682829 DOI: 10.1016/j.lssr.2022.07.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/23/2022] [Accepted: 07/26/2022] [Indexed: 06/17/2023]
Abstract
Exposure to ionizing radiation is considered by NASA to be a major health hazard for deep space exploration missions. Ionizing radiation sensitivity is modulated by both genomic and environmental factors. Understanding their contributions is crucial for designing experiments in model organisms, evaluating the risk of deep space (i.e. high-linear energy transfer, or LET, particle) radiation exposure in astronauts, and also selecting therapeutic irradiation regimes for cancer patients. We identified single nucleotide polymorphisms in 15 strains of mice, including 10 collaborative cross model strains and 5 founder strains, associated with spontaneous and ionizing radiation-induced in vitro DNA damage quantified based on immunofluorescent tumor protein p53 binding protein (53BP1) positive nuclear foci. Statistical analysis suggested an association with pathways primarily related to cellular signaling, metabolism, tumorigenesis and nervous system damage. We observed different genomic associations in early (4 and 8 h) responses to different LET radiation, while later (24 hour) DNA damage responses showed a stronger overlap across all LETs. Furthermore, a subset of pathways was associated with spontaneous DNA damage, suggesting 53BP1 positive foci as a potential biomarker for DNA integrity in mouse models. Our results suggest several mouse strains as new models to further study the impact of ionizing radiation and validate the identified genetic loci. We also highlight the importance of future human in vitro studies to refine the association of genes and pathways with the DNA damage response to ionizing radiation and identify targets for space travel countermeasures.
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Affiliation(s)
- Egle Cekanaviciute
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - Duc Tran
- Department of Computer Science and Engineering, University of Nevada, Reno, NV 89557, USA
| | - Hung Nguyen
- Department of Computer Science and Engineering, University of Nevada, Reno, NV 89557, USA
| | - Alejandra Lopez Macha
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA 94035, USA; Blue Marble Space Institute of Science, 600 1st Avenue, 1st Floor, Seattle, WA 98104, USA
| | - Eloise Pariset
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA 94035, USA; Universities Space Research Association, 615 National Avenue, Mountain View, CA 94043, USA
| | - Sasha Langley
- Molecular and Cell Biology, UC Berkeley, Berkeley, CA 94720, USA, and Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, USA
| | - Giulia Babbi
- Bologna Biocomputing Group, FABIT, University of Bologna, Via Belmeloro 6, Bologna, Italy
| | - Sherina Malkani
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA 94035, USA; Blue Marble Space Institute of Science, 600 1st Avenue, 1st Floor, Seattle, WA 98104, USA
| | - Sébastien Penninckx
- Molecular and Cell Biology, UC Berkeley, Berkeley, CA 94720, USA, and Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, USA; Medical Physics Department, Jules Bordet Institute, Université Libre de Bruxelles, 90 Rue Meylemeersch, 1070 Brussels, Belgium
| | - Jonathan C Schisler
- McAllister Heart Institute and Department of Pharmacology, The University of North Carolina at Chapel Hill, NC 27599, USA
| | - Tin Nguyen
- Department of Computer Science and Engineering, University of Nevada, Reno, NV 89557, USA
| | - Gary H Karpen
- Molecular and Cell Biology, UC Berkeley, Berkeley, CA 94720, USA, and Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, USA
| | - Sylvain V Costes
- Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA 94035, USA.
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14
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Badesso S, Cartas-Cejudo P, Espelosin M, Santamaria E, Cuadrado-Tejedor M, Garcia-Osta A. Docosahexaenoic Acid Ameliorates Contextual Fear Memory Deficits in the Tg2576 Alzheimer's Disease Mouse Model: Cellular and Molecular Correlates. Pharmaceutics 2022; 15:pharmaceutics15010082. [PMID: 36678710 PMCID: PMC9866126 DOI: 10.3390/pharmaceutics15010082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/09/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Docosahexaenoic acid (DHA), the most abundant polyunsaturated fatty acid in the brain, is essential for successful aging. In fact, epidemiological studies have demonstrated that increased intake of DHA might lower the risk for developing Alzheimer's disease (AD). These observations are supported by studies in animal models showing that DHA reduces synaptic pathology and memory deficits. Different mechanisms to explain these beneficial effects have been proposed; however, the molecular pathways involved are still unknown. In this study, to unravel the main underlying molecular mechanisms activated upon DHA treatment, the effect of a high dose of DHA on cognitive function and AD pathology was analyzed in aged Tg2576 mice and their wild-type littermates. Transcriptomic analysis of mice hippocampi using RNA sequencing was subsequently performed. Our results revealed that, through an amyloid-independent mechanism, DHA enhanced memory function and increased synapse formation only in the Tg2576 mice. Likewise, the IPA analysis demonstrated that essential neuronal functions related to synaptogenesis, neuritogenesis, the branching of neurites, the density of dendritic spines and the outgrowth of axons were upregulated upon-DHA treatment in Tg2576 mice. Our results suggest that memory function in APP mice is influenced by DHA intake; therefore, a high dose of daily DHA should be tested as a dietary supplement for AD dementia prevention.
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Affiliation(s)
- Sara Badesso
- Neurosciences Program, Center for Applied Medical Research (CIMA), University of Navarra, IdiSNA, 31008 Pamplona, Spain
| | - Paz Cartas-Cejudo
- Clinical Neuroproteomics Unit, Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, 31008 Pamplona, Spain
| | - Maria Espelosin
- Neurosciences Program, Center for Applied Medical Research (CIMA), University of Navarra, IdiSNA, 31008 Pamplona, Spain
| | - Enrique Santamaria
- Clinical Neuroproteomics Unit, Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, 31008 Pamplona, Spain
| | - Mar Cuadrado-Tejedor
- Neurosciences Program, Center for Applied Medical Research (CIMA), University of Navarra, IdiSNA, 31008 Pamplona, Spain
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, IdiSNA, 31008 Pamplona, Spain
- Correspondence: (M.C.-T.); (A.G.-O.)
| | - Ana Garcia-Osta
- Neurosciences Program, Center for Applied Medical Research (CIMA), University of Navarra, IdiSNA, 31008 Pamplona, Spain
- Correspondence: (M.C.-T.); (A.G.-O.)
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15
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Non-alcoholic fatty liver disease and liver secretome. Arch Pharm Res 2022; 45:938-963. [PMCID: PMC9703441 DOI: 10.1007/s12272-022-01419-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 11/15/2022] [Indexed: 11/29/2022]
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16
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Interaction kinetics between p115-RhoGEF and Gα 13 are determined by unique molecular interactions affecting agonist sensitivity. Commun Biol 2022; 5:1287. [PMID: 36434027 PMCID: PMC9700851 DOI: 10.1038/s42003-022-04224-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 11/04/2022] [Indexed: 11/27/2022] Open
Abstract
The three RH-RhoGEFs (Guanine nucleotide exchange factors) p115-RhoGEF, LARG (leukemia-associated RhoGEF) and PDZ-RhoGEF link G-protein coupled receptors (GPCRs) with RhoA signaling through activation of Gα12/13. In order to find functional differences in signaling between the different RH-RhoGEFs we examined their interaction with Gα13 in high spatial and temporal resolution, utilizing a FRET-based single cell assay. We found that p115-RhoGEF interacts significantly shorter with Gα13 than LARG and PDZ-RhoGEF, while narrowing the structural basis for these differences down to a single amino acid in the rgRGS domain of p115-RhoGEF. The mutation of this amino acid led to an increased interaction time with Gα13 and an enhanced agonist sensitivity, comparable to LARG, while mutating the corresponding amino acid in Gα13 the same effect could be achieved. While the rgRGS domains of RH-RhoGEFs showed GAP (GTPase-activating protein) activity towards Gα13 in vitro, our approach suggests higher GAP activity of p115-RhoGEF in intact cells.
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17
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Zhang H, Ren L, Shivnaraine RV. Targeting GPCRs to treat cardiac fibrosis. Front Cardiovasc Med 2022; 9:1011176. [PMID: 36277752 PMCID: PMC9582444 DOI: 10.3389/fcvm.2022.1011176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Cardiac fibrosis occurs ubiquitously in ischemic heart failure, genetic cardiomyopathies, diabetes mellitus, and aging. It triggers myocardial stiffness, which impairs cardiac function, ultimately progressing to end-stage heart failure and increased mortality. Although several targets for anti-fibrotic therapies have been identified, including TGF-β and receptor tyrosine kinase, there is currently no FDA-approved drug specifically targeting cardiac fibrosis. G protein-coupled receptors (GPCRs) are integral, multipass membrane-bound receptors that exhibit diverse and cell-specific expression, offering novel and unrealized therapeutic targets for cardiac fibrosis. This review highlights the emerging roles of several GPCRs and briefly explores their downstream pathways that are crucial in cardiac fibrosis. We will not only provide an overview of the GPCRs expressed on cardiac fibroblasts that are directly involved in myofibroblast activation but also describe those GPCRs which contribute to cardiac fibrosis via indirect crosstalk mechanisms. We also discuss the challenges of identifying novel effective therapies for cardiac fibrosis and offer strategies to circumvent these challenges.
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Affiliation(s)
- Hao Zhang
- Department of Medicine, Division of Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University, Stanford, CA, United States,*Correspondence: Hao Zhang
| | - Lu Ren
- Department of Medicine, Division of Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University, Stanford, CA, United States
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18
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Ringuet MT, Furness JB, Furness SGB. G protein-coupled receptor interactions and modification of signalling involving the ghrelin receptor, GHSR1a. J Neuroendocrinol 2022; 34:e13077. [PMID: 34931385 DOI: 10.1111/jne.13077] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/05/2021] [Indexed: 12/28/2022]
Abstract
The growth hormone secretagogue receptor 1a (GHSR1a) is intriguing because of its potential as a therapeutic target and its diverse molecular interactions. Initial studies of the receptor focused on the potential therapeutic ability for growth hormone (GH) release to reduce wasting in aging individuals, as well as food intake regulation for treatment of cachexia. Known roles of GHSR1a now extend to regulation of neurogenesis, learning and memory, gastrointestinal motility, glucose/lipid metabolism, the cardiovascular system, neuronal protection, motivational salience, and hedonic feeding. Ghrelin, the endogenous agonist of GHSR1a, is primarily located in the stomach and is absent from the central nervous system (CNS), including the spinal cord. However, ghrelin in the circulation does have access to a small number of CNS sites, including the arcuate nucleus, which is important in feeding control. At some sites, such as at somatotrophs, GHSR1a has high constitutive activity. Typically, ghrelin-dependent and constitutive GHSR1a activation occurs via Gαq/11 pathways. In vitro and in vivo data suggest that GHSR1a heterodimerises with multiple G protein-coupled receptors (GPCRs), including dopamine D1 and D2, serotonin 2C, orexin, oxytocin and melanocortin 3 receptors (MCR3), as well as the MCR3 accessory protein, MRAP2, providing possible mechanisms for its many physiological effects. In all cases, the receptor interaction changes downstream signalling and the responses to receptor agonists. This review discusses the signalling mechanisms of GHSR1a alone and in combination with other GPCRs, and explores the physiological consequences of GHSR1a coupling with other GPCRs.
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Affiliation(s)
- Mitchell Ty Ringuet
- Department of Anatomy and Physiology, University of Melbourne, Parkville, VIC, Australia
| | - John Barton Furness
- Department of Anatomy and Physiology, University of Melbourne, Parkville, VIC, Australia
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
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19
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Weatherly SM, Collin GB, Charette JR, Stone L, Damkham N, Hyde LF, Peterson JG, Hicks W, Carter GW, Naggert JK, Krebs MP, Nishina PM. Identification of Arhgef12 and Prkci as genetic modifiers of retinal dysplasia in the Crb1rd8 mouse model. PLoS Genet 2022; 18:e1009798. [PMID: 35675330 PMCID: PMC9212170 DOI: 10.1371/journal.pgen.1009798] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 06/21/2022] [Accepted: 05/03/2022] [Indexed: 12/03/2022] Open
Abstract
Mutations in the apicobasal polarity gene CRB1 lead to diverse retinal diseases, such as Leber congenital amaurosis, cone-rod dystrophy, retinitis pigmentosa (with and without Coats-like vasculopathy), foveal retinoschisis, macular dystrophy, and pigmented paravenous chorioretinal atrophy. Limited correlation between disease phenotypes and CRB1 alleles, and evidence that patients sharing the same alleles often present with different disease features, suggest that genetic modifiers contribute to clinical variation. Similarly, the retinal phenotype of mice bearing the Crb1 retinal degeneration 8 (rd8) allele varies with genetic background. Here, we initiated a sensitized chemical mutagenesis screen in B6.Cg-Crb1rd8/Pjn, a strain with a mild clinical presentation, to identify genetic modifiers that cause a more severe disease phenotype. Two models from this screen, Tvrm266 and Tvrm323, exhibited increased retinal dysplasia. Genetic mapping with high-throughput exome and candidate-gene sequencing identified causative mutations in Arhgef12 and Prkci, respectively. Epistasis analysis of both strains indicated that the increased dysplastic phenotype required homozygosity of the Crb1rd8 allele. Retinal dysplastic lesions in Tvrm266 mice were smaller and caused less photoreceptor degeneration than those in Tvrm323 mice, which developed an early, large diffuse lesion phenotype. At one month of age, Müller glia and microglia mislocalization at dysplastic lesions in both modifier strains was similar to that in B6.Cg-Crb1rd8/Pjn mice but photoreceptor cell mislocalization was more extensive. External limiting membrane disruption was comparable in Tvrm266 and B6.Cg-Crb1rd8/Pjn mice but milder in Tvrm323 mice. Immunohistological analysis of mice at postnatal day 0 indicated a normal distribution of mitotic cells in Tvrm266 and Tvrm323 mice, suggesting normal early development. Aberrant electroretinography responses were observed in both models but functional decline was significant only in Tvrm323 mice. These results identify Arhgef12 and Prkci as modifier genes that differentially shape Crb1-associated retinal disease, which may be relevant to understanding clinical variability and underlying disease mechanisms in humans. Inherited eye diseases affect roughly 1:1,000 individuals worldwide. Although these diseases are often linked to variants of a single gene, it is increasingly recognized that a second variant in other genes may modify disease characteristics, including age of onset, severity, and lesion appearance. Identifying such modifier genes in humans is difficult. In this study, two modifiers of a gene associated with retinal damage leading to childhood blindness in humans (CRB1) were identified in mice. Retinal damage caused by Crb1 mutation alone was less severe than in the presence of Arhgef12 or Prkci mutations. Furthermore, the modifier gene mutations caused retinal damage only in the presence of the Crb1 mutation. Our results point to a role of mouse Crb1 and the modifying effects of Arhgef12 and Prkci in a biological network that controls adhesive interactions between cells. The variation in disease severity, lesion appearance, and visual responses in these mice provide a dramatic example of modifier gene influence. This work may lead to an improved understanding of the molecular basis of CRB1-associated retinal disease, with possible relevance to diagnostic and therapeutic intervention in humans.
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Affiliation(s)
| | - Gayle B. Collin
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | | | - Lisa Stone
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Nattaya Damkham
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Graduate Program in Immunology, Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
- Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Lillian F. Hyde
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | | | - Wanda Hicks
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | | | | | - Mark P. Krebs
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- * E-mail: (MPK); (PMN)
| | - Patsy M. Nishina
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- * E-mail: (MPK); (PMN)
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20
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Ito MA, Kojima E, Yanagihara Y, Yoshida K, Matsuoka I. Differential Effects of Gq Protein-Coupled Uridine Receptor Stimulation on IL-8 Production in 1321N1 Human Astrocytoma Cells. Biol Pharm Bull 2022; 45:691-697. [PMID: 35650097 DOI: 10.1248/bpb.b21-01020] [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: 11/22/2022]
Abstract
G-protein-coupled receptors (GPCRs) trigger various physiological functions. GPCR-mediated effects largely depend on the receptor-associated G-protein subtypes. However, compelling evidence suggests that single receptor proteins activate multiple G-protein subtypes to induce diverse physiological responses. This study compared responses mediated by three different Gq-binding uridine nucleotide receptors, P2Y2, P2Y4, and P2Y6, by measuring Ca2+ signaling and interleukin (IL)-8 production. In 1321N1 human astrocytoma cells stably expressing these receptors, agonist stimulation evoked concentration-dependent intracellular Ca2+ elevation to a similar extent. In contrast, agonist-induced IL-8 production was prominent in P2Y6-expressing cells, but not in P2Y2- and P2Y4-expressing cells. In addition to inhibition of Gq signaling, G12 signal blockade attenuated uridine 5'-diphosphate (UDP)-induced IL-8 production, suggesting the involvement of a small G-protein pathway. The Rac inhibitor EHop-16 prevented UDP-induced IL-8 release. The P2Y6-triggered IL-8 production was also inhibited by extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and protein kinase B (Akt) inhibitors. These results suggest that P2Y6 receptor-induced IL-8 production requires Gq-mediated Ca2+ signaling as well as G12-mediated activation of Rac. The results also suggest the importance of considering the involvement of multiple G proteins in understanding GPCR-mediated functions.
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Affiliation(s)
- Masa-Aki Ito
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Erika Kojima
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Yu Yanagihara
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Kazuki Yoshida
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
| | - Isao Matsuoka
- Laboratory of Pharmacology, Faculty of Pharmacy, Takasaki University of Health and Welfare
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21
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Voss JH, Mahardhika AB, Inoue A, Müller CE. Agonist-Dependent Coupling of the Promiscuous Adenosine A 2B Receptor to Gα Protein Subunits. ACS Pharmacol Transl Sci 2022; 5:373-386. [PMID: 35592437 PMCID: PMC9112290 DOI: 10.1021/acsptsci.2c00020] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Indexed: 12/28/2022]
Abstract
The adenosine A2B receptor (A2BAR) belongs to the rhodopsin-like G protein-coupled receptor (GPCR) family. It is upregulated under hypoxic conditions, in inflammation and cancer. Previous studies indicated the coupling of the A2BAR to different G proteins, mainly Gs, but in some cases Gq/11 or Gi, depending on the cell type. We have now utilized novel technologies, (i) heterologous expression of individual members of the Gαq/11 protein family (Gαq, Gα11, Gα14, and Gα15) in Gαq/11 knockout cells, and (ii) the TRUPATH platform, allowing the direct observation of Gα protein activation for each of the Gα subunits by bioluminescence resonance energy transfer (BRET) measurements. Three structurally diverse A2BAR agonists were studied: the cognate agonist adenosine, its metabolically stable analog NECA, and the non-nucleosidic partial agonist BAY 60-6583. Adenosine and NECA activated most members of all four Gα protein families (Gαs, Gαq/11, Gαi, and Gα12/13). Significant differences in potencies and efficacies were observed; the highest efficacies were determined at the Gα15, Gαs, and Gα12 proteins, and for NECA additionally at the Gαi2 protein. In contrast, the partial agonist BAY 60-6583 only activated Gα15, Gαs, and Gα12 proteins. Adenosine deaminase, an allosteric modulator of ARs, selectively increased the potency and efficacy of NECA and BAY 60-6583 at the Gα15 protein, while it had no effect or decreased efficacy at the other Gα proteins. We conclude that the A2BAR is preferably coupled to the Gα15, Gαs, and Gα12 proteins. Upon upregulation of receptor or Gα protein expression, coupling to further Gα proteins likely occurs. Importantly, different agonists can display different activation profiles.
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Affiliation(s)
- Jan Hendrik Voss
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Andhika B Mahardhika
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany.,Research Training Group GRK1873, University of Bonn, D-53121 Bonn, Germany
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Christa E Müller
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany.,Research Training Group GRK1873, University of Bonn, D-53121 Bonn, Germany
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22
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Melick CH, Lama-Sherpa TD, Curukovic A, Jewell JL. G-Protein Coupled Receptor Signaling and Mammalian Target of Rapamycin Complex 1 Regulation. Mol Pharmacol 2022; 101:181-190. [PMID: 34965982 PMCID: PMC9092479 DOI: 10.1124/molpharm.121.000302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 11/29/2021] [Indexed: 11/30/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) senses upstream stimuli to regulate numerous cellular functions such as metabolism, growth, and autophagy. Increased activation of mTOR complex 1 (mTORC1) is typically observed in human disease and continues to be an important therapeutic target. Understanding the upstream regulators of mTORC1 will provide a crucial link in targeting hyperactivated mTORC1 in human disease. In this mini-review, we will discuss the regulation of mTORC1 by upstream stimuli, with a specific focus on G-protein coupled receptor signaling to mTORC1. SIGNIFICANCE STATEMENT: mTORC1 is a master regulator of many cellular processes and is often hyperactivated in human disease. Therefore, understanding the molecular underpinnings of G-protein coupled receptor signaling to mTORC1 will undoubtedly be beneficial for human disease.
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Affiliation(s)
- Chase H Melick
- Department of Molecular Biology, Harold C. Simmons Comprehensive Cancer, and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Tshering D Lama-Sherpa
- Department of Molecular Biology, Harold C. Simmons Comprehensive Cancer, and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Adna Curukovic
- Department of Molecular Biology, Harold C. Simmons Comprehensive Cancer, and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Jenna L Jewell
- Department of Molecular Biology, Harold C. Simmons Comprehensive Cancer, and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
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23
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Discovery of a functionally selective ghrelin receptor (GHSR 1a) ligand for modulating brain dopamine. Proc Natl Acad Sci U S A 2022; 119:e2112397119. [PMID: 35239443 PMCID: PMC8915830 DOI: 10.1073/pnas.2112397119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The modulation of growth hormone secretagogue receptor-1a (GHSR1a) signaling is a promising strategy for treating brain conditions of metabolism, aging, and addiction. GHSR1a activation results in pleiotropic physiological outcomes through distinct and pharmacologically separable G protein– and β-arrestin (βarr)–dependent signaling pathways. Thus, pathway-selective modulation can enable improved pharmacotherapeutics that can promote therapeutic efficacy while mitigating side effects. Here, we describe the discovery of a brain-penetrant small molecule, N8279 (NCATS-SM8864), that biases GHSR1a conformations toward Gαq activation and reduces aberrant dopaminergic behavior in mice. N8279 represents a promising chemical scaffold to advance the development of better treatments for GHSR1a-related brain disorders involving the pathological dysregulation of dopamine. The growth hormone secretagogue receptor-1a (GHSR1a) is the cognate G protein–coupled receptor (GPCR) for the peptide hormone ghrelin. GHSR1a is a promising therapeutic target for a wide range of metabolic, age-related, and central nervous system (CNS)–based conditions. In addition, growing evidence supports that GHSR1a is a modulator of dopamine (DA) homeostasis and is neuroprotective within brain DA circuits. GHSR1a signaling originates from pharmacologically separable G protein– and β-arrestin (βarr)–dependent pathways, and consequently, GHSR1a-mediated physiological responses depend upon their distinctive signaling contributions. Thus, when treating disorders of disrupted DA homeostasis, a pharmacological strategy that modulates biased GHSR1a signaling may uncouple desired therapeutic outcomes from unwanted side effects. Here, we report the discovery of a small molecule GHSR1a agonist, N8279 (NCATS-SM8864), functionally selective for G protein signaling. Comprehensive pharmacological characterization reveals that N8279 elicits potent Gαq activity at the apo- and ghrelin-bound GHSR1a. Further biochemical analysis and molecular modeling demonstrate that N8279 signaling requires the extracellular domain of GHSR1a, especially extracellular loop 2. Collectively, these findings suggest that N8279 possesses an extended binding mode into the extracellular vestibule of the GHSR1a that preferentially favors Gαq signaling over alternative G proteins and βarr2-dependent cellular responses. Critically, N8279 is brain-penetrant in mice, exhibits CNS stability, and attenuates dysfunctional DA-mediated behaviors in both genetic and pharmacological mouse models of hyperdopaminergia. Our findings provide insight into the mechanisms governing GPCR functional selectivity and emphasize how biased ligand drug development can produce novel GHSR1a pharmacotherapeutics to treat pathological disruptions of brain DA homeostasis.
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24
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Rasheed SAK, Subramanyan LV, Lim WK, Udayappan UK, Wang M, Casey PJ. The emerging roles of Gα12/13 proteins on the hallmarks of cancer in solid tumors. Oncogene 2022; 41:147-158. [PMID: 34689178 PMCID: PMC8732267 DOI: 10.1038/s41388-021-02069-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 09/28/2021] [Accepted: 10/06/2021] [Indexed: 01/14/2023]
Abstract
G12 proteins comprise a subfamily of G-alpha subunits of heterotrimeric GTP-binding proteins (G proteins) that link specific cell surface G protein-coupled receptors (GPCRs) to downstream signaling molecules and play important roles in human physiology. The G12 subfamily contains two family members: Gα12 and Gα13 (encoded by the GNA12 and GNA13 genes, respectively) and, as with all G proteins, their activity is regulated by their ability to bind to guanine nucleotides. Increased expression of both Gα12 and Gα13, and their enhanced signaling, has been associated with tumorigenesis and tumor progression of multiple cancer types over the past decade. Despite these strong associations, Gα12/13 proteins are underappreciated in the field of cancer. As our understanding of G protein involvement in oncogenic signaling has evolved, it has become clear that Gα12/13 signaling is pleotropic and activates specific downstream effectors in different tumor types. Further, the expression of Gα12/13 proteins is regulated through a series of transcriptional and post-transcriptional mechanisms, several of which are frequently deregulated in cancer. With the ever-increasing understanding of tumorigenic processes driven by Gα12/13 proteins, it is becoming clear that targeting Gα12/13 signaling in a context-specific manner could provide a new strategy to improve therapeutic outcomes in a number of solid tumors. In this review, we detail how Gα12/13 proteins, which were first discovered as proto-oncogenes, are now known to drive several "classical" hallmarks, and also play important roles in the "emerging" hallmarks, of cancer.
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Affiliation(s)
| | | | - Wei Kiang Lim
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Udhaya Kumari Udayappan
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Mei Wang
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Patrick J Casey
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, 169857, Singapore.
- Dept. of Pharmacology and Cancer Biology, Duke Univ. Medical Center, Durham, NC, 27710, USA.
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25
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Wei L, Shi J. Insight Into Rho Kinase Isoforms in Obesity and Energy Homeostasis. Front Endocrinol (Lausanne) 2022; 13:886534. [PMID: 35769086 PMCID: PMC9234286 DOI: 10.3389/fendo.2022.886534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/06/2022] [Indexed: 11/13/2022] Open
Abstract
Obesity and associated complications increasingly jeopardize global health and contribute to the rapidly rising prevalence of type 2 diabetes mellitus and obesity-related diseases. Developing novel methods for the prevention and treatment of excess body adipose tissue expansion can make a significant contribution to public health. Rho kinase is a Rho-associated coiled-coil-containing protein kinase (Rho kinase or ROCK). The ROCK family including ROCK1 and ROCK2 has recently emerged as a potential therapeutic target for the treatment of metabolic disorders. Up-regulated ROCK activity has been involved in the pathogenesis of all aspects of metabolic syndrome including obesity, insulin resistance, dyslipidemia and hypertension. The RhoA/ROCK-mediated actin cytoskeleton dynamics have been implicated in both white and beige adipogenesis. Studies using ROCK pan-inhibitors in animal models of obesity, diabetes, and associated complications have demonstrated beneficial outcomes. Studies via genetically modified animal models further established isoform-specific roles of ROCK in the pathogenesis of metabolic disorders including obesity. However, most reported studies have been focused on ROCK1 activity during the past decade. Due to the progress in developing ROCK2-selective inhibitors in recent years, a growing body of evidence indicates more attention should be devoted towards understanding ROCK2 isoform function in metabolism. Hence, studying individual ROCK isoforms to reveal their specific roles and principal mechanisms in white and beige adipogenesis, insulin sensitivity, energy balancing regulation, and obesity development will facilitate significant breakthroughs for systemic treatment with isoform-selective inhibitors. In this review, we give an overview of ROCK functions in the pathogenesis of obesity and insulin resistance with a particular focus on the current understanding of ROCK isoform signaling in white and beige adipogenesis, obesity and thermogenesis in adipose tissue and other major metabolic organs involved in energy homeostasis regulation.
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Affiliation(s)
- Lei Wei
- *Correspondence: Lei Wei, ; Jianjian Shi,
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26
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Targeting the Ghrelin Receptor as a Novel Therapeutic Option for Epilepsy. Biomedicines 2021; 10:biomedicines10010053. [PMID: 35052733 PMCID: PMC8773216 DOI: 10.3390/biomedicines10010053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/22/2021] [Accepted: 12/24/2021] [Indexed: 12/12/2022] Open
Abstract
Epilepsy is a neurological disease affecting more than 50 million individuals worldwide. Notwithstanding the availability of a broad array of antiseizure drugs (ASDs), 30% of patients suffer from pharmacoresistant epilepsy. This highlights the urgent need for novel therapeutic options, preferably with an emphasis on new targets, since “me too” drugs have been shown to be of no avail. One of the appealing novel targets for ASDs is the ghrelin receptor (ghrelin-R). In epilepsy patients, alterations in the plasma levels of its endogenous ligand, ghrelin, have been described, and various ghrelin-R ligands are anticonvulsant in preclinical seizure and epilepsy models. Up until now, the exact mechanism-of-action of ghrelin-R-mediated anticonvulsant effects has remained poorly understood and is further complicated by multiple downstream signaling pathways and the heteromerization properties of the receptor. This review compiles current knowledge, and discusses the potential mechanisms-of-action of the anticonvulsant effects mediated by the ghrelin-R.
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27
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Bettegazzi B, Bellani S, Cattaneo S, Codazzi F, Grohovaz F, Zacchetti D. Gα13 Contributes to LPS-Induced Morphological Alterations and Affects Migration of Microglia. Mol Neurobiol 2021; 58:6397-6414. [PMID: 34529232 DOI: 10.1007/s12035-021-02553-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 08/26/2021] [Indexed: 11/24/2022]
Abstract
Microglia are the resident immune cells of the CNS that are activated in response to a variety of stimuli. This phenotypical change is aimed to maintain the local homeostasis, also by containing the insults and repair the damages. All these processes are tightly regulated and coordinated and a failure in restoring homeostasis by microglia can result in the development of neuroinflammation that can facilitate the progression of pathological conditions. Indeed, chronic microglia activation is commonly recognized as a hallmark of many neurological disorders, especially at an early stage. Many complex pathways, including cytoskeletal remodeling, are involved in the control of the microglial phenotypical and morphological changes that occur during activation. In this work, we focused on the small GTPase Gα13 and its role at the crossroad between RhoA and Rac1 signaling when microglia is exposed to pro-inflammatory stimulation. We propose the direct involvement of Gα13 in the cytoskeletal rearrangements mediated by FAK, LIMK/cofilin, and Rac1 during microglia activation. In fact, we show that Gα13 knockdown significantly inhibited LPS-induced microglial cell activation, in terms of both changes in morphology and migration, through the modulation of FAK and one of its downstream effectors, Rac1. In conclusion, we propose Gα13 as a critical factor in the regulation of morphological and functional properties of microglia during activation, which might become a target of intervention for the control of microglia inflammation.
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Affiliation(s)
- Barbara Bettegazzi
- IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy.
- Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy.
| | - Serena Bellani
- IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Stefano Cattaneo
- IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
- Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy
| | - Franca Codazzi
- IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
- Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy
| | - Fabio Grohovaz
- IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
- Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy
| | - Daniele Zacchetti
- IRCCS San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy.
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28
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Knerr JM, Kledal TN, Rosenkilde MM. Molecular Properties and Therapeutic Targeting of the EBV-Encoded Receptor BILF1. Cancers (Basel) 2021; 13:4079. [PMID: 34439235 PMCID: PMC8392491 DOI: 10.3390/cancers13164079] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/05/2021] [Accepted: 08/09/2021] [Indexed: 12/12/2022] Open
Abstract
The γ-herpesvirus Epstein-Barr Virus (EBV) establishes lifelong infections in approximately 90% of adults worldwide. Up to 1,000,000 people yearly are estimated to suffer from health conditions attributed to the infection with this virus, such as nasopharyngeal and gastric carcinomas as well as several forms of B, T and NK cell lymphoma. To date, no EBV-specific therapeutic option has reached the market, greatly reducing the survival prognoses of affected patients. Similar to other herpesviruses, EBV encodes for a G protein-coupled receptor (GPCR), BILF1, affecting a multitude of cellular signaling pathways. BILF1 has been identified to promote immune evasion and tumorigenesis, effectively ensuring a life-long persistence of EBV in, and driving detrimental health conditions to its host. This review summarizes the epidemiology of EBV-associated malignancies, their current standard-of-care, EBV-specific therapeutics in development, GPCRs and their druggability, and most importantly consolidates the findings of over 15 years of research on BILF1 in the context of EBV-specific drug development. Taken together, BILF1 constitutes a promising target for the development of novel EBV-specific therapeutics.
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Affiliation(s)
- Julius Maximilian Knerr
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, University of Copenhagen, 2200 København, Denmark;
| | | | - Mette Marie Rosenkilde
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, University of Copenhagen, 2200 København, Denmark;
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29
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van der Westhuizen ET, Choy KHC, Valant C, McKenzie-Nickson S, Bradley SJ, Tobin AB, Sexton PM, Christopoulos A. Fine Tuning Muscarinic Acetylcholine Receptor Signaling Through Allostery and Bias. Front Pharmacol 2021; 11:606656. [PMID: 33584282 PMCID: PMC7878563 DOI: 10.3389/fphar.2020.606656] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/30/2020] [Indexed: 12/18/2022] Open
Abstract
The M1 and M4 muscarinic acetylcholine receptors (mAChRs) are highly pursued drug targets for neurological diseases, in particular for Alzheimer's disease and schizophrenia. Due to high sequence homology, selective targeting of any of the M1-M5 mAChRs through the endogenous ligand binding site has been notoriously difficult to achieve. With the discovery of highly subtype selective mAChR positive allosteric modulators in the new millennium, selectivity through targeting an allosteric binding site has opened new avenues for drug discovery programs. However, some hurdles remain to be overcome for these promising new drug candidates to progress into the clinic. One challenge is the potential for on-target side effects, such as for the M1 mAChR where over-activation of the receptor by orthosteric or allosteric ligands can be detrimental. Therefore, in addition to receptor subtype selectivity, a drug candidate may need to exhibit a biased signaling profile to avoid such on-target adverse effects. Indeed, recent studies in mice suggest that allosteric modulators for the M1 mAChR that bias signaling toward specific pathways may be therapeutically important. This review brings together details on the signaling pathways activated by the M1 and M4 mAChRs, evidence of biased agonism at these receptors, and highlights pathways that may be important for developing new subtype selective allosteric ligands to achieve therapeutic benefit.
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Affiliation(s)
- Emma T. van der Westhuizen
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - K. H. Christopher Choy
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Celine Valant
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Simon McKenzie-Nickson
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Sophie J. Bradley
- Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Andrew B. Tobin
- Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Patrick M. Sexton
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
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30
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Wimalasiri-Yapa BMCR, Barrero RA, Stassen L, Hafner LM, McGraw EA, Pyke AT, Jansen CC, Suhrbier A, Yakob L, Hu W, Devine GJ, Frentiu FD. Temperature modulates immune gene expression in mosquitoes during arbovirus infection. Open Biol 2021; 11:200246. [PMID: 33401993 PMCID: PMC7881175 DOI: 10.1098/rsob.200246] [Citation(s) in RCA: 15] [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: 08/12/2020] [Accepted: 12/04/2020] [Indexed: 12/20/2022] Open
Abstract
The principal vector of dengue, Zika and chikungunya viruses is the mosquito Aedes aegypti, with its ability to transmit pathogens influenced by ambient temperature. We use chikungunya virus (CHIKV) to understand how the mosquito transcriptome responds to arbovirus infection at different ambient temperatures. We exposed CHIKV-infected mosquitoes to 18, 28 and 32°C, and found that higher temperature correlated with higher virus levels, particularly at 3 days post infection, but lower temperature resulted in reduced virus levels. RNAseq analysis indicated significantly altered gene expression levels in CHIKV infection. The highest number of significantly differentially expressed genes was observed at 28°C, with a more muted effect at the other temperatures. At the higher temperature, the expression of many classical immune genes, including Dicer-2, was not substantially altered in response to CHIKV. The upregulation of Toll, IMD and JAK-STAT pathways was only observed at 28°C. Functional annotations suggested that genes in immune response and metabolic pathways related to energy supply and DNA replication were involved in temperature-dependent changes. Time post infection also led to substantially different gene expression profiles, and this varied with temperature. In conclusion, temperature significantly modulates mosquito gene expression in response to infection, potentially leading to impairment of immune defences at higher temperatures.
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Affiliation(s)
- B. M. C. Randika Wimalasiri-Yapa
- Institute of Health and Biomedical Innovation, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
- Department of Medical Laboratory Sciences, Faculty of Health Science, Open University of Sri Lanka, Nugegoda, Colombo, Sri Lanka
| | - Roberto A. Barrero
- eResearch Office, Division of Research and Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Liesel Stassen
- Institute of Health and Biomedical Innovation, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Louise M. Hafner
- Institute of Health and Biomedical Innovation, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Elizabeth A. McGraw
- Center for Infectious Disease Dynamics, Department of Entomology, The Pennsylvania State University, University Park, PA 16801, USA
| | - Alyssa T. Pyke
- Public Health Virology Laboratory, Forensic and Scientific Services, Coopers Plains, Queensland, Australia
| | - Cassie C. Jansen
- Communicable Diseases Branch, Department of Health, Queensland Government, Herston, Queensland, Australia
| | - Andreas Suhrbier
- Inflammation Biology, QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4006, Australia
| | - Laith Yakob
- London School of Hygiene and Tropical Medicine, London, UK
| | - Wenbiao Hu
- School of Public Health and Social Work, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Gregor J. Devine
- Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Francesca D. Frentiu
- Institute of Health and Biomedical Innovation, and School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
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31
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Melick CH, Jewell JL. Regulation of mTORC1 by Upstream Stimuli. Genes (Basel) 2020; 11:genes11090989. [PMID: 32854217 PMCID: PMC7565831 DOI: 10.3390/genes11090989] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/22/2020] [Accepted: 08/23/2020] [Indexed: 01/08/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) is an evolutionary conserved Ser/Thr protein kinase that senses multiple upstream stimuli to control cell growth, metabolism, and autophagy. mTOR is the catalytic subunit of mTOR complex 1 (mTORC1). A significant amount of research has uncovered the signaling pathways regulated by mTORC1, and the involvement of these signaling cascades in human diseases like cancer, diabetes, and ageing. Here, we review advances in mTORC1 regulation by upstream stimuli. We specifically focus on how growth factors, amino acids, G-protein coupled receptors (GPCRs), phosphorylation, and small GTPases regulate mTORC1 activity and signaling.
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Affiliation(s)
- Chase H. Melick
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA;
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jenna L. Jewell
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA;
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Correspondence:
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32
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Vizurraga A, Adhikari R, Yeung J, Yu M, Tall GG. Mechanisms of adhesion G protein-coupled receptor activation. J Biol Chem 2020; 295:14065-14083. [PMID: 32763969 DOI: 10.1074/jbc.rev120.007423] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/31/2020] [Indexed: 12/19/2022] Open
Abstract
Adhesion G protein-coupled receptors (AGPCRs) are a thirty-three-member subfamily of Class B GPCRs that control a wide array of physiological processes and are implicated in disease. AGPCRs uniquely contain large, self-proteolyzing extracellular regions that range from hundreds to thousands of residues in length. AGPCR autoproteolysis occurs within the extracellular GPCR autoproteolysis-inducing (GAIN) domain that is proximal to the N terminus of the G protein-coupling seven-transmembrane-spanning bundle. GAIN domain-mediated self-cleavage is constitutive and produces two-fragment holoreceptors that remain bound at the cell surface. It has been of recent interest to understand how AGPCRs are activated in relation to their two-fragment topologies. Dissociation of the AGPCR fragments stimulates G protein signaling through the action of the tethered-peptide agonist stalk that is occluded within the GAIN domain in the holoreceptor form. AGPCRs can also signal independently of fragment dissociation, and a few receptors possess GAIN domains incapable of self-proteolysis. This has resulted in complex theories as to how these receptors are activated in vivo, complicating pharmacological advances. Currently, there is no existing structure of an activated AGPCR to support any of the theories. Further confounding AGPCR research is that many of the receptors remain orphans and lack identified activating ligands. In this review, we provide a detailed layout of the current theorized modes of AGPCR activation with discussion of potential parallels to mechanisms used by other GPCR classes. We provide a classification means for the ligands that have been identified and discuss how these ligands may activate AGPCRs in physiological contexts.
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Affiliation(s)
- Alexander Vizurraga
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Rashmi Adhikari
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Jennifer Yeung
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Maiya Yu
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Gregory G Tall
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
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33
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Rehman A, Baloch NUA, Morrow JP, Pacher P, Haskó G. Targeting of G-protein coupled receptors in sepsis. Pharmacol Ther 2020; 211:107529. [PMID: 32197794 PMCID: PMC7388546 DOI: 10.1016/j.pharmthera.2020.107529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/11/2020] [Accepted: 03/11/2020] [Indexed: 12/11/2022]
Abstract
The Third International Consensus Definitions (Sepsis-3) define sepsis as life-threatening multi-organ dysfunction caused by a dysregulated host response to infection. Sepsis can progress to septic shock-an even more lethal condition associated with profound circulatory, cellular and metabolic abnormalities. Septic shock remains a leading cause of death in intensive care units and carries a mortality of almost 25%. Despite significant advances in our understanding of the pathobiology of sepsis, therapeutic interventions have not translated into tangible differences in the overall outcome for patients. Clinical trials of antagonists of various pro-inflammatory mediators in sepsis have been largely unsuccessful in the past. Given the diverse physiologic roles played by G-protein coupled receptors (GPCR), modulation of GPCR signaling for the treatment of sepsis has also been explored. Traditional pharmacologic approaches have mainly focused on ligands targeting the extracellular domains of GPCR. However, novel techniques aimed at modulating GPCR intracellularly through aptamers, pepducins and intrabodies have opened a fresh avenue of therapeutic possibilities. In this review, we summarize the diverse roles played by various subfamilies of GPCR in the pathogenesis of sepsis and identify potential targets for pharmacotherapy through these novel approaches.
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Affiliation(s)
- Abdul Rehman
- Department of Medicine, Rutgers-New Jersey Medical School, Newark, NJ, United States
| | - Noor Ul-Ain Baloch
- Department of Medicine, Rutgers-New Jersey Medical School, Newark, NJ, United States
| | - John P Morrow
- Department of Medicine, Columbia University, New York City, NY, United States
| | - Pál Pacher
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institutes of Health, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | - György Haskó
- Department of Anesthesiology, Columbia University, New York City, NY, United States.
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34
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Yang YM, Kuen DS, Chung Y, Kurose H, Kim SG. Gα 12/13 signaling in metabolic diseases. Exp Mol Med 2020; 52:896-910. [PMID: 32576930 PMCID: PMC7338450 DOI: 10.1038/s12276-020-0454-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 05/04/2020] [Accepted: 05/11/2020] [Indexed: 12/12/2022] Open
Abstract
As the key governors of diverse physiological processes, G protein-coupled receptors (GPCRs) have drawn attention as primary targets for several diseases, including diabetes and cardiovascular disease. Heterotrimeric G proteins converge signals from ~800 members of the GPCR family. Among the members of the G protein α family, the Gα12 family members comprising Gα12 and Gα13 have been referred to as gep oncogenes. Gα12/13 levels are altered in metabolic organs, including the liver and muscles, in metabolic diseases. The roles of Gα12/13 in metabolic diseases have been investigated. In this review, we highlight findings demonstrating Gα12/13 amplifying or dampening regulators of phenotype changes. We discuss the molecular basis of G protein biology in the context of posttranslational modifications to heterotrimeric G proteins and the cell signaling axis. We also highlight findings providing insights into the organ-specific, metabolic and pathological roles of G proteins in changes associated with specific cells, energy homeostasis, glucose metabolism, liver fibrosis and the immune and cardiovascular systems. This review summarizes the currently available knowledge on the importance of Gα12/13 in the physiology and pathogenesis of metabolic diseases, which is presented according to the basic understanding of their metabolic actions and underlying cellular and molecular bases. Understanding the activities of two members of a vital category of proteins called G proteins, which initiate metabolic changes when signaling molecules bind to cells, could lead to new therapies for many diseases. Researchers in South Korea and Japan, led by Sang Geon Kim at Seoul National University, review the significance of the Gα12 and Gα13 proteins in diseases characterised by significant changes in metabolism, including liver conditions and disorders of the cardiovascular and immune systems. Specific roles for the proteins have been identified by a variety of methods, including studying the effect of disabling the genes that code for them in mice. Recent insights suggest that drugs interfering with the activity of these Gα proteins might help treat many conditions in which the molecular signalling networks involving the proteins are disrupted.
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Affiliation(s)
- Yoon Mee Yang
- College of Pharmacy, Kangwon National University, Chuncheon, 24341, South Korea
| | - Da-Sol Kuen
- College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Yeonseok Chung
- College of Pharmacy, Seoul National University, Seoul, 08826, South Korea
| | - Hitoshi Kurose
- Department of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Sang Geon Kim
- College of Pharmacy, Seoul National University, Seoul, 08826, South Korea.
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35
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Girard M, Dagenais Bellefeuille S, Eiselt É, Brouillette R, Placet M, Arguin G, Longpré JM, Sarret P, Gendron FP. The P2Y 6 receptor signals through Gα q /Ca 2+ /PKCα and Gα 13 /ROCK pathways to drive the formation of membrane protrusions and dictate cell migration. J Cell Physiol 2020; 235:9676-9690. [PMID: 32420639 DOI: 10.1002/jcp.29779] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/09/2020] [Accepted: 05/01/2020] [Indexed: 12/14/2022]
Abstract
Cell migration is a ubiquitous process necessary to maintain and restore tissue functions. However, in cancer, cell migration leads to metastasis development and thus worsens the prognosis. Although the mechanism of cell migration is well understood, the identification of new targets modulating cell migration and deciphering their signaling events could lead to new therapies to restore tissue functions in diseases, such as inflammatory bowel disease, or to block metastatic development in different forms of cancer. Previous research has identified the G-protein-coupled P2Y6 receptor as an innovative target that could dictate cell migration under normal and pathological conditions. Surprisingly, there is little information on the cellular events triggered by activated P2Y6 during cell migration. Here, we demonstrated that P2Y6 activation stimulated A549 human lung cancer cells and Caco-2 colorectal cancer cell migration. Activated P2Y6 increased the number of filopodia and focal adhesions; two migratory structures required for cell migration. The generation of these structures involved Gαq /calcium/protein kinases C (PKC) and Gα13 /RHO-associated protein kinase-dependent pathways that dictate the formation of the migratory structures. These pathways led to the stabilization of the actin cytoskeleton through a PKC-dependent phosphorylation of cofilin. These results support the idea that the P2Y6 receptor represents a target of interest to modulate cell migration and revealed an intricate dialogue between two Gα-protein signaling pathways.
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Affiliation(s)
- Mélissa Girard
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Steve Dagenais Bellefeuille
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Émilie Eiselt
- Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Rebecca Brouillette
- Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Morgane Placet
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Guillaume Arguin
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Jean-Michel Longpré
- Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Philippe Sarret
- Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Fernand-Pierre Gendron
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada.,Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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Stecky RC, Quick CR, Fleming TL, Mull ML, Vinson VK, Whitley MS, Dover EN, Meigs TE. Divergent C-terminal motifs in Gα12 and Gα13 provide distinct mechanisms of effector binding and SRF activation. Cell Signal 2020; 72:109653. [PMID: 32330601 DOI: 10.1016/j.cellsig.2020.109653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/19/2020] [Accepted: 04/19/2020] [Indexed: 11/18/2022]
Abstract
The G12/13 subfamily of heterotrimeric guanine nucleotide binding proteins comprises the α subunits Gα12 and Gα13, which transduce signals for cell growth, cytoskeletal rearrangements, and oncogenic transformation. In an increasing range of cancers, overexpressed Gα12 or Gα13 are implicated in aberrant cell proliferation and/or metastatic invasion. Although Gα12 and Gα13 bind non-redundant sets of effector proteins and participate in unique signalling pathways, the structural features responsible for functional differences between these α subunits are largely unknown. Invertebrates encode a single G12/13 homolog that participates in cytoskeletal changes yet appears to lack signalling to SRF (serum response factor), a transcriptional activator stimulated by mammalian Gα12 and Gα13 to promote growth and tumorigenesis. Our previous studies identified an evolutionarily divergent region in Gα12 for which replacement by homologous sequence from Drosophila melanogaster abolished SRF signalling, whereas the same invertebrate substitution was fully tolerated in Gα13 [Montgomery et al. (2014) Mol. Pharmacol. 85: 586]. These findings prompted our current approach of evolution-guided mutagenesis to identify fine structural features of Gα12 and Gα13 that underlie their respective SRF activation mechanisms. Our results identified two motifs flanking the α4 helix that play a key role in Gα12 signalling to SRF. We found the region encompassing these motifs to provide an interacting surface for multiple Gα12-specific target proteins that fail to bind Gα13. Adjacent to this divergent region, a highly-conserved domain was vital for SRF activation by both Gα12 and Gα13. However, dissection of this domain using invertebrate substitutions revealed different signalling mechanisms in these α subunits and identified Gα13-specific determinants of binding Rho-specific guanine nucleotide exchange factors. Furthermore, invertebrate substitutions in the C-terminal, α5 helical region were selectively disruptive to Gα12 signalling. Taken together, our results identify key structural features near the C-terminus that evolved after the divergence of Gα12 and Gα13, and should aid the development of agents to selectively manipulate signalling by individual α subunits of the G12/13 subfamily.
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Affiliation(s)
- Rebecca C Stecky
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - Courtney R Quick
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - Todd L Fleming
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - Makenzy L Mull
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - Vanessa K Vinson
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - Megan S Whitley
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - E Nicole Dover
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America
| | - Thomas E Meigs
- Department of Biology, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States of America.
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Hedegaard MA, Holst B. The Complex Signaling Pathways of the Ghrelin Receptor. Endocrinology 2020; 161:5734640. [PMID: 32049280 DOI: 10.1210/endocr/bqaa020] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 02/10/2020] [Indexed: 12/13/2022]
Abstract
The ghrelin receptor (GhrR) is known for its strong orexigenic effects in pharmacological doses and has long been considered as a promising target for the treatment of obesity. Several antagonists have been developed to decrease the orexigenic signaling, but none of these have been approved for the treatment of obesity because of adverse effects and lack of efficacy. Heterodimerization and biased signaling are important concepts for G-protein coupled receptor (GPCR) signaling, and the influence of these aspects on the GhrR may be important for feeding behavior and obesity. GhrR has been described to heterodimerize with other GPCRs, such as the dopamine receptors 1 and 2, leading to a modulation of the signaling properties of both dimerization partners. Another complicating factor of GhrR-mediated signaling is its ability to activate several different signaling pathways on ligand stimulation. Importantly, some ligands have shown to be "biased" or "functionally selective," implying that the ligand favors a particular signaling pathway. These unique signaling properties could have a sizeable impact on the physiological functions of the GhrR system. Importantly, heterodimerization may explain why the GhrR is expressed in areas of the brain that are difficult for peptide ligands to access. One possibility is that the purpose of GhrR expression is to modulate the function of other receptors in addition to merely being independently activated. We suggest that a deeper understanding of the signaling properties of the GhrR will facilitate future drug discovery in the areas of obesity and weight management.
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Affiliation(s)
- Morten Adler Hedegaard
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Birgitte Holst
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
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38
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Johnson AC, Wu W, Attipoe EM, Sasser JM, Taylor EB, Showmaker KC, Kyle PB, Lindsey ML, Garrett MR. Loss of Arhgef11 in the Dahl Salt-Sensitive Rat Protects Against Hypertension-Induced Renal Injury. Hypertension 2020; 75:1012-1024. [PMID: 32148127 DOI: 10.1161/hypertensionaha.119.14338] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Arhgef11 is a Rho-guanine nucleotide exchange factor that was previously implicated in kidney injury in the Dahl salt-sensitive (SS) rat, a model of hypertension-related chronic kidney disease. Reduced Arhgef11 expression in an SS-Arhgef11SHR-minimal congenic strain (spontaneously hypertensive rat allele substituted for S allele) significantly decreased proteinuria, fibrosis, and improved renal hemodynamics, without impacting blood pressure compared with the control SS (SS-wild type). Here, SS-Arhgef11-/- and SS-wild type rats were placed on either low or elevated salt (0.3% or 2% NaCl) from 4 to 12 weeks of age. On low salt, starting at week 6 and through week 12, SS-Arhgef11-/- animals demonstrated a 3-fold decrease in proteinuria compared with SS-wild type. On high salt, beginning at week 6, SS-Arhgef11-/- animals demonstrated >2-fold lower proteinuria from weeks 8 to 12 and 30 mm Hg lower BP compared with SS-wild type. To better understand the molecular mechanisms of the renal protection from loss of Arhgef11, both RNA sequencing and discovery proteomics were performed on kidneys from week 4 (before onset of renal injury/proteinuria between groups) and at week 12 (low salt). The omics data sets revealed loss of Arhgef11 (SS-Arhgef11-/-) initiates early transcriptome/protein changes in the cytoskeleton starting as early as week 4 that impact a number of cellular functions, including actin cytoskeletal regulation, mitochondrial metabolism, and solute carrier transporters. In summary, in vivo phenotyping coupled with a multi-omics approach provides strong evidence that increased Arhgef11 expression in the Dahl SS rat leads to actin cytoskeleton-mediated changes in cell morphology and cell function that promote kidney injury, hypertension, and decline in kidney function.
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Affiliation(s)
- Ashley C Johnson
- From the Department of Pharmacology and Toxicology (A.C.J., W.W., E.M.A., J.M.S., M.R.G., K.C.S.), University of Mississippi Medical Center
| | - Wenjie Wu
- From the Department of Pharmacology and Toxicology (A.C.J., W.W., E.M.A., J.M.S., M.R.G., K.C.S.), University of Mississippi Medical Center
| | - Esinam M Attipoe
- From the Department of Pharmacology and Toxicology (A.C.J., W.W., E.M.A., J.M.S., M.R.G., K.C.S.), University of Mississippi Medical Center
| | - Jennifer M Sasser
- From the Department of Pharmacology and Toxicology (A.C.J., W.W., E.M.A., J.M.S., M.R.G., K.C.S.), University of Mississippi Medical Center
| | - Erin B Taylor
- Department of Physiology (E.B.T., M.L.L.), University of Mississippi Medical Center
| | - Kurt C Showmaker
- From the Department of Pharmacology and Toxicology (A.C.J., W.W., E.M.A., J.M.S., M.R.G., K.C.S.), University of Mississippi Medical Center
| | - Patrick B Kyle
- Department of Pathology (P.B.K.), University of Mississippi Medical Center
| | - Merry L Lindsey
- Department of Physiology (E.B.T., M.L.L.), University of Mississippi Medical Center
| | - Michael R Garrett
- From the Department of Pharmacology and Toxicology (A.C.J., W.W., E.M.A., J.M.S., M.R.G., K.C.S.), University of Mississippi Medical Center.,Department of Medicine (Nephrology) (M.R.G.), University of Mississippi Medical Center
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39
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Tutunea-Fatan E, Lee JC, Denker BM, Gunaratnam L. Heterotrimeric Gα 12/13 proteins in kidney injury and disease. Am J Physiol Renal Physiol 2020; 318:F660-F672. [PMID: 31984793 DOI: 10.1152/ajprenal.00453.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Gα12 and Gα13 are ubiquitous members of the heterotrimeric guanine nucleotide-binding protein (G protein) family that play central and integrative roles in the regulation of signal transduction cascades within various cell types in the kidney. Gα12/Gα13 proteins enable the kidney to adapt to an ever-changing environment by transducing stimuli from cell surface receptors and accessory proteins to effector systems. Therefore, perturbations in Gα12/Gα13 levels or their activity can contribute to the pathogenesis of various renal diseases, including renal cancer. This review will highlight and discuss the complex and expanding roles of Gα12/Gα13 proteins on distinct renal pathologies, with emphasis on more recently reported findings. Deciphering how the different Gα12/Gα13 interaction networks participate in the onset and development of renal diseases may lead to the discovery of new therapeutic strategies.
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Affiliation(s)
- Elena Tutunea-Fatan
- Matthew Mailing Centre for Translational Transplant Studies, Lawson Health Research Institute, London, Ontario, Canada
| | - Jasper C Lee
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Bradley M Denker
- Beth Israel Deaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Lakshman Gunaratnam
- Matthew Mailing Centre for Translational Transplant Studies, Lawson Health Research Institute, London, Ontario, Canada.,Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada.,Division of Nephrology, Department of Medicine, University of Western Ontario, London, Ontario, Canada
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40
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Lim WK, Chai X, Ghosh S, Ray D, Wang M, Rasheed SAK, Casey PJ. Gα-13 induces C XC motif chemokine ligand 5 expression in prostate cancer cells by transactivating NF-κB. J Biol Chem 2019; 294:18192-18206. [PMID: 31636124 PMCID: PMC6885619 DOI: 10.1074/jbc.ra119.010018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/03/2019] [Indexed: 12/24/2022] Open
Abstract
GNA13, the α subunit of a heterotrimeric G protein, mediates signaling through G-protein-coupled receptors (GPCRs). GNA13 is up-regulated in many solid tumors, including prostate cancer, where it contributes to tumor initiation, drug resistance, and metastasis. To better understand how GNA13 contributes to tumorigenesis and tumor progression, we compared the entire transcriptome of PC3 prostate cancer cells with those cells in which GNA13 expression had been silenced. This analysis revealed that GNA13 levels affected multiple CXC-family chemokines. Further investigation in three different prostate cancer cell lines singled out pro-tumorigenic CXC motif chemokine ligand 5 (CXCL5) as a target of GNA13 signaling. Elevation of GNA13 levels consistently induced CXCL5 RNA and protein expression in all three cell lines. Analysis of the CXCL5 promoter revealed that the -505/+62 region was both highly active and influenced by GNA13, and a single NF-κB site within this region of the promoter was critical for GNA13-dependent promoter activity. ChIP experiments revealed that, upon induction of GNA13 expression, occupancy at the CXCL5 promoter was significantly enriched for the p65 component of NF-κB. GNA13 knockdown suppressed both p65 phosphorylation and the activity of a specific NF-κB reporter, and p65 silencing impaired the GNA13-enhanced expression of CXCL5. Finally, blockade of Rho GTPase activity eliminated the impact of GNA13 on NF-κB transcriptional activity and CXCL5 expression. Together, these findings suggest that GNA13 drives CXCL5 expression by transactivating NF-κB in a Rho-dependent manner in prostate cancer cells.
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Affiliation(s)
- Wei Kiang Lim
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857 Singapore
| | - Xiaoran Chai
- Programme in Cardiovascular and Metabolic Disorders, Duke-NUS Medical School, 169857 Singapore
| | - Sujoy Ghosh
- Programme in Cardiovascular and Metabolic Disorders, Duke-NUS Medical School, 169857 Singapore
| | - Debleena Ray
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857 Singapore
| | - Mei Wang
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857 Singapore
| | | | - Patrick J Casey
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857 Singapore; Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710.
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41
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Ceritinib-Induced Regression of an Insulin-Like Growth Factor-Driven Neuroepithelial Brain Tumor. Int J Mol Sci 2019; 20:ijms20174267. [PMID: 31480400 PMCID: PMC6747232 DOI: 10.3390/ijms20174267] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/15/2019] [Accepted: 08/28/2019] [Indexed: 12/25/2022] Open
Abstract
The insulin-like growth factor (IGF) pathway plays an important role in several brain tumor entities. However, the lack of inhibitors crossing the blood–brain barrier remains a significant obstacle for clinical translation. Here, we targeted the IGF pathway using ceritinib, an off-target inhibitor of the IGF1 receptor (IGF1R) and insulin receptor (INSR), in a pediatric patient with an unclassified brain tumor and a notch receptor 1 (NOTCH1) germline mutation. Pathway analysis of the tumor revealed activation of the sonic hedgehog (SHH), the wingless and integrated-1 (WNT), the IGF, and the Notch pathway. The proliferation of the patient tumor cells (225ZL) was inhibited by arsenic trioxide (ATO), which is an inhibitor of the SHH pathway, by linsitinib, which is an inhibitor of IGF1R and INSR, and by ceritinib. 225ZL expressed INSR but not IGF1R at the protein level, and ceritinib blocked the phosphorylation of INSR. Our first personalized treatment included ATO, but because of side effects, we switched to ceritinib. After 46 days, we achieved a concentration of 1.70 µM of ceritinib in the plasma, and after 58 days, MRI confirmed that there was a response to the treatment. Ceritinib accumulated in the tumor at a concentration of 2.72 µM. Our data suggest ceritinib as a promising drug for the treatment of IGF-driven brain tumors.
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42
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Fang Z, Pyne S, Pyne NJ. WITHDRAWN: Ceramide and Sphingosine 1-Phosphate in adipose dysfunction. Prog Lipid Res 2019:100991. [PMID: 31442525 DOI: 10.1016/j.plipres.2019.100991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/21/2019] [Accepted: 04/01/2019] [Indexed: 11/18/2022]
Affiliation(s)
- Zijian Fang
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161, Cathedral St, Glasgow, G4 0RE, Scotland, UK
| | - Susan Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161, Cathedral St, Glasgow, G4 0RE, Scotland, UK
| | - Nigel J Pyne
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161, Cathedral St, Glasgow, G4 0RE, Scotland, UK
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43
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Biringer RG. The Role of Eicosanoids in Alzheimer's Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16142560. [PMID: 31323750 PMCID: PMC6678666 DOI: 10.3390/ijerph16142560] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/09/2019] [Accepted: 07/13/2019] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is one of the most common neurodegenerative disorders known. Estimates from the Alzheimer's Association suggest that there are currently 5.8 million Americans living with the disease and that this will rise to 14 million by 2050. Research over the decades has revealed that AD pathology is complex and involves a number of cellular processes. In addition to the well-studied amyloid-β and tau pathology, oxidative damage to lipids and inflammation are also intimately involved. One aspect all these processes share is eicosanoid signaling. Eicosanoids are derived from polyunsaturated fatty acids by enzymatic or non-enzymatic means and serve as short-lived autocrine or paracrine agents. Some of these eicosanoids serve to exacerbate AD pathology while others serve to remediate AD pathology. A thorough understanding of eicosanoid signaling is paramount for understanding the underlying mechanisms and developing potential treatments for AD. In this review, eicosanoid metabolism is examined in terms of in vivo production, sites of production, receptor signaling, non-AD biological functions, and known participation in AD pathology.
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Affiliation(s)
- Roger G Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, 5000 Lakewood Ranch Blvd., Bradenton, FL 34211, USA.
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Strassheim D, Gerasimovskaya E, Irwin D, Dempsey EC, Stenmark K, Karoor V. RhoGTPase in Vascular Disease. Cells 2019; 8:E551. [PMID: 31174369 PMCID: PMC6627336 DOI: 10.3390/cells8060551] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/24/2019] [Accepted: 05/27/2019] [Indexed: 12/24/2022] Open
Abstract
Ras-homologous (Rho)A/Rho-kinase pathway plays an essential role in many cellular functions, including contraction, motility, proliferation, and apoptosis, inflammation, and its excessive activity induces oxidative stress and promotes the development of cardiovascular diseases. Given its role in many physiological and pathological functions, targeting can result in adverse effects and limit its use for therapy. In this review, we have summarized the role of RhoGTPases with an emphasis on RhoA in vascular disease and its impact on endothelial, smooth muscle, and heart and lung fibroblasts. It is clear from the various studies that understanding the regulation of RhoGTPases and their regulators in physiology and pathological conditions is required for effective targeting of Rho.
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Affiliation(s)
- Derek Strassheim
- Cardiovascular and Pulmonary Research Lab, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
| | - Evgenia Gerasimovskaya
- Cardiovascular and Pulmonary Research Lab, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
- Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
| | - David Irwin
- Cardiovascular and Pulmonary Research Lab, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
| | - Edward C Dempsey
- Cardiovascular and Pulmonary Research Lab, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
- Pulmonary Sciences and Critical Care Medicine, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA.
| | - Kurt Stenmark
- Cardiovascular and Pulmonary Research Lab, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
- Department of Pediatrics, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
| | - Vijaya Karoor
- Cardiovascular and Pulmonary Research Lab, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
- Pulmonary Sciences and Critical Care Medicine, Department of Medicine, Anschutz Medical Campus, University of Colorado, Aurora, CO 80045, USA.
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Inoue A, Raimondi F, Kadji FMN, Singh G, Kishi T, Uwamizu A, Ono Y, Shinjo Y, Ishida S, Arang N, Kawakami K, Gutkind JS, Aoki J, Russell RB. Illuminating G-Protein-Coupling Selectivity of GPCRs. Cell 2019; 177:1933-1947.e25. [PMID: 31160049 DOI: 10.1016/j.cell.2019.04.044] [Citation(s) in RCA: 325] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/28/2019] [Accepted: 04/25/2019] [Indexed: 12/20/2022]
Abstract
Heterotrimetic G proteins consist of four subfamilies (Gs, Gi/o, Gq/11, and G12/13) that mediate signaling via G-protein-coupled receptors (GPCRs), principally by receptors binding Gα C termini. G-protein-coupling profiles govern GPCR-induced cellular responses, yet receptor sequence selectivity determinants remain elusive. Here, we systematically quantified ligand-induced interactions between 148 GPCRs and all 11 unique Gα subunit C termini. For each receptor, we probed chimeric Gα subunit activation via a transforming growth factor-α (TGF-α) shedding response in HEK293 cells lacking endogenous Gq/11 and G12/13 proteins, and complemented G-protein-coupling profiles through a NanoBiT-G-protein dissociation assay. Interrogation of the dataset identified sequence-based coupling specificity features, inside and outside the transmembrane domain, which we used to develop a coupling predictor that outperforms previous methods. We used the predictor to engineer designer GPCRs selectively coupled to G12. This dataset of fine-tuned signaling mechanisms for diverse GPCRs is a valuable resource for research in GPCR signaling.
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Affiliation(s)
- Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan; Advanced Research & Development Programs for Medical Innovation (PRIME), Japan Agency for Medical Research and Development (AMED), Chiyoda-ku, Tokyo 100-0004, Japan; Advanced Research & Development Programs for Medical Innovation (LEAP), AMED, Chiyoda-ku, Tokyo 100-0004, Japan.
| | - Francesco Raimondi
- CellNetworks, Bioquant, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany; Biochemie Zentrum Heidelberg (BZH), Heidelberg University, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany.
| | | | - Gurdeep Singh
- CellNetworks, Bioquant, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany; Biochemie Zentrum Heidelberg (BZH), Heidelberg University, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
| | - Takayuki Kishi
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Akiharu Uwamizu
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Yuki Ono
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Yuji Shinjo
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Satoru Ishida
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Nadia Arang
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kouki Kawakami
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - J Silvio Gutkind
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan; Advanced Research & Development Programs for Medical Innovation (LEAP), AMED, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Robert B Russell
- CellNetworks, Bioquant, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany; Biochemie Zentrum Heidelberg (BZH), Heidelberg University, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany.
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Kahl DJ, Hutchings KM, Lisabeth EM, Haak AJ, Leipprandt JR, Dexheimer T, Khanna D, Tsou PS, Campbell PL, Fox DA, Wen B, Sun D, Bailie M, Neubig RR, Larsen SD. 5-Aryl-1,3,4-oxadiazol-2-ylthioalkanoic Acids: A Highly Potent New Class of Inhibitors of Rho/Myocardin-Related Transcription Factor (MRTF)/Serum Response Factor (SRF)-Mediated Gene Transcription as Potential Antifibrotic Agents for Scleroderma. J Med Chem 2019; 62:4350-4369. [PMID: 30951312 PMCID: PMC6590913 DOI: 10.1021/acs.jmedchem.8b01772] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Through a phenotypic high-throughput screen using a serum response element luciferase promoter, we identified a novel 5-aryl-1,3,4-oxadiazol-2-ylthiopropionic acid lead inhibitor of Rho/myocardin-related transcription factor (MRTF)/serum response factor (SRF)-mediated gene transcription with good potency (IC50 = 180 nM). We were able to rapidly improve the cellular potency by 5 orders of magnitude guided by sharply defined and synergistic SAR. The remarkable potency and depth of the SAR, as well as the relatively low molecular weight of the series, suggests, but does not prove, that binding to the unknown molecular target may be occurring through a covalent mechanism. The series nevertheless has no observable cytotoxicity up to 100 μM. Ensuing pharmacokinetic optimization resulted in the development of two potent and orally bioavailable anti-fibrotic agents that were capable of dose-dependently reducing connective tissue growth factor gene expression in vitro as well as significantly reducing the development of bleomycin-induced dermal fibrosis in mice in vivo.
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Affiliation(s)
| | | | - Erika Mathes Lisabeth
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Andrew J Haak
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Jeffrey R Leipprandt
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Thomas Dexheimer
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Dinesh Khanna
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - Pei-Suen Tsou
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - Phillip L Campbell
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - David A Fox
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | | | | | - Marc Bailie
- Michigan State University in Vivo Facility , East Lansing , Michigan 48824 , United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
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Ceramide and sphingosine 1-phosphate in adipose dysfunction. Prog Lipid Res 2019; 74:145-159. [PMID: 30951736 DOI: 10.1016/j.plipres.2019.04.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/21/2019] [Accepted: 04/01/2019] [Indexed: 12/17/2022]
Abstract
The increased adipose tissue mass of obese individuals enhances the risk of metabolic syndrome, type 2 diabetes and cardiovascular diseases. During pathological expansion of adipose tissue, multiple molecular controls of lipid storage, adipocyte turn-over and endocrine secretion are perturbed and abnormal lipid metabolism results in a distinct lipid profile. There is a role for ceramides and sphingosine 1-phosphate (S1P) in inducing adipose dysfunction. For instance, the alteration of ceramide biosynthesis, through the de-regulation of key enzymes, results in aberrant formation of ceramides (e.g. C16:0 and C18:0) which block insulin signaling and promote adipose inflammation. Furthermore, S1P can induce defective adipose tissue phenotypes by promoting chronic inflammation and inhibiting adipogenesis. These abnormal changes are discussed in the context of possible therapeutic approaches to re-establish normal adipose function and to, thereby, increase insulin sensitivity in type 2 diabetes. Such novel approaches include blockade of ceramide biosynthesis using inhibitors of sphingomyelinase or dihydroceramide desaturase and by antagonism of S1P receptors, such as S1P2.
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Toro-Tapia G, Villaseca S, Beyer A, Roycroft A, Marcellini S, Mayor R, Torrejón M. The Ric-8A/Gα13/FAK signalling cascade controls focal adhesion formation during neural crest cell migration in Xenopus. Development 2018; 145:dev.164269. [PMID: 30297374 DOI: 10.1242/dev.164269] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 09/23/2018] [Indexed: 12/22/2022]
Abstract
Ric-8A is a pleiotropic guanine nucleotide exchange factor involved in the activation of various heterotrimeric G-protein pathways during adulthood and early development. Here, we sought to determine the downstream effectors of Ric-8A during the migration of the vertebrate cranial neural crest (NC) cells. We show that the Gα13 knockdown phenocopies the Ric-8A morphant condition, causing actin cytoskeleton alteration, protrusion instability, and a strong reduction in the number and dynamics of focal adhesions. In addition, the overexpression of Gα13 is sufficient to rescue Ric-8A-depleted cells. Ric-8A and Gα13 physically interact and colocalize in protrusions of the cells leading edge. The focal adhesion kinase FAK colocalizes and interacts with the endogenous Gα13, and a constitutively active form of Src efficiently rescues the Gα13 morphant phenotype in NC cells. We propose that Ric-8A-mediated Gα13 signalling is required for proper cranial NC cell migration by regulating focal adhesion dynamics and protrusion formation.
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Affiliation(s)
- Gabriela Toro-Tapia
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4030000, Chile
| | - Soraya Villaseca
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4030000, Chile
| | - Andrea Beyer
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4030000, Chile
| | - Alice Roycroft
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Sylvain Marcellini
- Departamento de Biología Cellular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4030000, Chile
| | - Roberto Mayor
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Marcela Torrejón
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4030000, Chile
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Li M, Lv Y, Chen F, Wang X, Zhu J, Li H, Xiao J. Co-stimulation of LPAR 1 and S1PR 1/3 increases the transplantation efficacy of human mesenchymal stem cells in drug-induced and alcoholic liver diseases. Stem Cell Res Ther 2018; 9:161. [PMID: 29898789 PMCID: PMC6000942 DOI: 10.1186/s13287-018-0860-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/13/2018] [Accepted: 04/03/2018] [Indexed: 02/08/2023] Open
Abstract
Background One of the major obstacles facing stem cell therapy is the limited number of functional stem cells available after transplantation due to the harsh microenvironment surrounding the damaged tissue. The aim of this study was to delineate the mechanistic involvement of lysophosphatidic acid receptors (LPARs) and sphingosine-1-phosphate receptors (S1PRs) in the regulation of anti-stress and transplantation efficacy of stem cells. Methods Human adipose-derived mesenchymal stem cells (hADMSCs) were treated with chemical toxin or ethanol to induce cell stress. Lysophosphatidic acid (LPA) and/or sphingosine-1-phosphate (S1P) were co-treated to examine their protective effects and mechanisms on stem cell damage. Acute liver failure and alcoholic liver disease murine models were also established to test the transplantation efficacy of hADMSCs with or without LPA/S1P pre-incubation. Results Co-stimulation of LPAR1 by LPA and S1PR1/3 by S1P synergistically enhanced the anti-stress ability of hADMSCs induced by chemical or ethanol incubation in vitro. Downstream pathways involved in this process included the Gi protein (but not the G12/13 proteins), the RAS/ERK pathway, and the PI3K/Akt pathway. Upon cell injury, the nuclear translocation of nuclear factor-kappa B (NF-κB) was promoted to facilitate the activation of downstream pro-inflammatory gene transcription, which was ameliorated by co-treatment with LPA and/or S1P. Increased secretion of interleukin (IL)-10 from stem cells by LPA and/or S1P seemed to be one of the major protective mechanisms since blocking IL-10 expression significantly aggravated stress-induced cell damage. In a drug-induced acute liver failure model and a chronic alcoholic liver disease model, pre-conditioning with LPA and/or S1P significantly enhanced the survival ratio and the therapeutic efficacy of hADMSCs in mice, including ameliorating histological damage, oxidative stress, inflammation, fibrosis, lipid metabolism dysfunction, and enhancing alcohol metabolizing enzyme activity. Importantly, supplementing LPA and/or S1P did not alter the basic characteristics of the hADMSCs nor induce tumour formation after cell transplantation. Conclusions Co-use of LPA and S1P represents a novel and safe strategy to enhance stem cell transplantation efficacy for future drug- and alcoholic-related liver disease therapies. Electronic supplementary material The online version of this article (10.1186/s13287-018-0860-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mianhuan Li
- Department of Gastroenterology, Clinical Medicine Research Institute, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, People's Republic of China.,State Key Discipline of Infectious Diseases, Department of Infectious Diseases, Shenzhen Third People's Hospital, Shenzhen, 518112, People's Republic of China
| | - Yi Lv
- Department of Gastroenterology, Clinical Medicine Research Institute, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, People's Republic of China
| | - Feng Chen
- State Key Discipline of Infectious Diseases, Department of Infectious Diseases, Shenzhen Third People's Hospital, Shenzhen, 518112, People's Republic of China
| | - Xiaoyan Wang
- Department of Gastroenterology, Clinical Medicine Research Institute, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, People's Republic of China
| | - Jiang Zhu
- JM Medical (Shenzhen), LLC, Shenzhen, Shenzhen, 518000, People's Republic of China
| | - Hao Li
- Department of Head and Neck Surgery, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Centre, Guangzhou, 510060, People's Republic of China.
| | - Jia Xiao
- Department of Gastroenterology, Clinical Medicine Research Institute, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, People's Republic of China. .,State Key Discipline of Infectious Diseases, Department of Infectious Diseases, Shenzhen Third People's Hospital, Shenzhen, 518112, People's Republic of China. .,School of Biomedical Sciences, The University of Hong Kong, Hong Kong, Hong Kong, Special Administrative Region of China.
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50
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Gastrin stimulates pancreatic cancer cell directional migration by activating the Gα12/13-RhoA-ROCK signaling pathway. Exp Mol Med 2018; 50:1-14. [PMID: 29717112 PMCID: PMC5938061 DOI: 10.1038/s12276-018-0081-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 02/02/2018] [Accepted: 02/05/2018] [Indexed: 12/24/2022] Open
Abstract
The mechanism by which gastrin promotes pancreatic cancer cell metastasis is unclear. The process of directing polarized cancer cells toward the extracellular matrix is principally required for invasion and distant metastasis; however, whether gastrin can induce this process and its underlying mechanism remain to be elucidated. In this study, we found that gastrin-induced phosphorylation of paxillin at tyrosine 31/118 and RhoA activation as well as promoted the metastasis of PANC-1 cancer cells. Depletion of Gα12 and Gα13 inhibited the phosphorylation of paxillin and downstream activation of GTP-RhoA, blocked the formation and aggregation of focal adhesions and facilitated polarization of actin filaments induced by gastrin. Suppression of RhoA and ROCK also exhibited identical results. Selective inhibition of the CCKBR–Gα12/13–RhoA–ROCK signaling pathway blocked the reoriented localization of the Golgi apparatus at the leading edge of migrated cancer cells. YM022 and Y-27632 significantly suppressed hepatic metastasis of orthotic pancreatic tumors induced by gastrin in vivo. Collectively, we demonstrate that gastrin promotes Golgi reorientation and directional polarization of pancreatic cancer cells by activation of paxillin via the CCKBR–Gα12/13–RhoA–ROCK signal pathway. A hormone found in high levels in pancreatic cancer sufferers helps the disease spread by co-ordinating cellular migration. Pancreatic cancer is one of the most deadly forms of cancer, being highly aggressive and likely to metastasize. Honggang Yu at Renmin Hospital of Wuhan University and scientists across China have demonstrated that gastrin, a hormone expressed at higher levels in patients with pancreatic cancer, helps to co-ordinate directional cell migration and ensure the disease spreads effectively. By activating two key molecules via a specific signalling pathway, gastrin ensures the correct orientation of the Golgi apparatus, a cellular organelle tasked with packaging proteins for transportation. This in turn activates directional migration of the cancer cells. The results explain why gastrin is over-expressed in both tumors and blood in cancer patients, and may inform future therapies.
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