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Luginina A, Maslov I, Khorn P, Volkov O, Khnykin A, Kuzmichev P, Shevtsov M, Belousov A, Kapranov I, Dashevskii D, Kornilov D, Bestsennaia E, Hofkens J, Hendrix J, Gensch T, Cherezov V, Ivanovich V, Mishin A, Borshchevskiy V. Functional GPCR Expression in Eukaryotic LEXSY System. J Mol Biol 2023; 435:168310. [PMID: 37806553 DOI: 10.1016/j.jmb.2023.168310] [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: 06/29/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/10/2023]
Abstract
G protein-coupled receptors (GPCRs) form the largest superfamily of membrane proteins in the human genome, and represent one of the most important classes of drug targets. Their structural studies facilitate rational drug discovery. However, atomic structures of only about 20% of human GPCRs have been solved to date. Recombinant production of GPCRs for structural studies at a large scale is challenging due to their low expression levels and stability. Therefore, in this study, we explored the efficacy of the eukaryotic system LEXSY (Leishmania tarentolae) for GPCR production. We selected the human A2A adenosine receptor (A2AAR), as a model protein, expressed it in LEXSY, purified it, and compared with the same receptor produced in insect cells, which is the most popular expression system for structural studies of GPCRs. The A2AAR purified from both expression systems showed similar purity, stability, ligand-induced conformational changes and structural dynamics, with a remarkably higher protein yield in the case of LEXSY expression. Overall, our results suggest that LEXSY is a promising platform for large-scale production of GPCRs for structural studies.
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Li H, Zhao J, Shi X. GPBAR1 Promotes Proliferation of Serous Ovarian Cancer by Inducing Smad4 Ubiquitination. Appl Immunohistochem Mol Morphol 2021; 29:519-526. [PMID: 33605573 DOI: 10.1097/pai.0000000000000917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 01/11/2021] [Indexed: 01/25/2023]
Abstract
BACKGROUND Ovarian cancer (OC) is the most lethal malignancy of all female cancers and lacks an effective prognostic biomarker. Serous ovarian cancer (SOC) is the most common OC histologic type. The expression and function of bile acid receptor, G-protein-coupled bile acid receptor-1 (GPBAR1), in tumor progression remains controversial, and its clinical significance in SOC is unclear. MATERIALS AND METHODS In our study, we detected the expression of GPBAR1 in SOCs and normal ovarian tissues with quantitative real-time polymerase chain reaction and immunohistochemistry to detect its expression pattern. Moreover, the prognostic significance of GPBAR1 was investigated with univariate and multivariate analyses. The function of GPBAR1 in regulating SOC proliferation was studied and the underlying mechanism was investigated with experiments in vitro. RESULTS GPBAR1 was overexpressed in SOCs compared with the normal ovarian tissues. In the 166 SOCs, subsets with low and high GPBAR1 accounted for 57.23% and 42.77%, respectively. Moreover, our results suggested that GPBAR1 expression was significantly associated with poor prognosis and can be considered as an independent prognostic biomarker. With experiments in vitro, we suggested that GPBAR1 promoted SOC proliferation by increasing Smad4 ubiquitination, which required the involvement of GPBAR1-induced ERK phosphorylation. CONCLUSIONS GPBAR1 was overexpressed in SOC and predicted the poor prognosis of SOC. We showed that GPBAR1 promoted SOC proliferation by activating ERK and ubiquitining Smad4. Our results suggested that GPBAR1 was a supplement to better classify SOC on the basis of the molecular profile and that GPBAR1 may be a potential drug target of SOC.
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Abiko LA, Rogowski M, Gautier A, Schertler G, Grzesiek S. Efficient production of a functional G protein-coupled receptor in E. coli for structural studies. JOURNAL OF BIOMOLECULAR NMR 2021; 75:25-38. [PMID: 33501610 PMCID: PMC7897205 DOI: 10.1007/s10858-020-00354-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/08/2020] [Indexed: 05/22/2023]
Abstract
G protein-coupled receptors (GPCRs) are transmembrane signal transducers which regulate many key physiological process. Since their discovery, their analysis has been limited by difficulties in obtaining sufficient amounts of the receptors in high-quality, functional form from heterologous expression hosts. Albeit highly attractive because of its simplicity and the ease of isotope labeling for NMR studies, heterologous expression of functional GPCRs in E. coli has proven particularly challenging due to the absence of the more evolved protein expression and folding machinery of higher eukaryotic hosts. Here we first give an overview on the previous strategies for GPCR E. coli expression and then describe the development of an optimized robust protocol for the E. coli expression and purification of two mutants of the turkey β1-adrenergic receptor (β1AR) uniformly or selectively labeled in 15N or 2H,15N. These mutants had been previously optimized for thermal stability using insect cell expression and used successfully in crystallographic and NMR studies. The same sequences were then used for E. coli expression. Optimization of E. coli expression was achieved by a quantitative analysis of losses of receptor material at each step of the solubilization and purification procedure. Final yields are 0.2-0.3 mg receptor per liter culture. Whereas both expressed mutants are well folded and competent for orthosteric ligand binding, the less stable YY-β1AR mutant also comprises the two native tyrosines Y5.58 and Y7.53, which enable G protein binding. High-quality 1H-15N TROSY spectra were obtained for E. coli-expressed YY-β1AR in three different functional states (antagonist, agonist, and agonist + G protein-mimicking nanobody-bound), which are identical to spectra obtained of the same forms of the receptor expressed in insect cells. NdeI and AgeI restriction sites introduced into the expression plasmid allow for the easy replacement of the receptor gene by other GPCR genes of interest, and the provided quantitative workflow analysis may guide the respective adaptation of the purification protocol.
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Xu D, Xie L, Zhang Z, Wang D, Qiu J, Yu W, Xu C, He C, Xu X, Yin J. Preliminary Investigation about the Expression of G Protein-Coupled Receptors in Platelets from Patients with Chronic Immune Thrombocytopenic Purpura. Acta Haematol 2021; 144:551-559. [PMID: 33849009 DOI: 10.1159/000514907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 02/02/2021] [Indexed: 02/05/2023]
Abstract
OBJECTIVE The objective of this study was to determine the expression of G protein-coupled receptors (GPCRs) in platelets from adult patients with chronic immune thrombocytopenic purpura (ITP). METHODS Peripheral blood samples were collected from 40 patients with chronic ITP in the Second Affiliated Hospital of Shantou University Medical College, and 40 peripheral blood samples from healthy volunteers were collected; expressions of the adenosine diphosphate receptors (P2Y1 and P2Y12), alpha-2A adrenergic receptor (α2A-AR), and thromboxane A2 receptor (TP) in platelets were detected by flow cytometry. Gα protein, protease-activated receptor 1 (PAR1), and protease-activated receptor 4 (PAR4) were analyzed by Western blot and analyzed statistically. RESULTS Flow cytometry measurements of mean fluorescence intensities showed platelets from patients with chronic ITP, compared to healthy individuals, had significantly higher levels of P2Y1 (31.4 ± 2.2 vs. 7.8 ± 0.8), P2Y12 (29.6 ± 2.1 vs. 7.2 ± 1.3), α2A-AR (25.8 ± 2.9 vs. 9.8 ± 0.9), and TP (39.8 ± 3.1 vs. 4.7 ± 0.6) (all p < 0.01). Similarly, integrated optical density analysis of Western blots showed that platelets from patients with chronic ITP had significantly higher levels of Gα (1046.3 ± 159.96 vs. 254.49 ± 39.51), PAR1 (832.98 ± 98.81 vs. 203.92 ± 27.47), and PAR4 (1518.80 ± 272.45 vs. 431.27 ± 41.86) (all p < 0.01). CONCLUSION Expression of GPCRs is increased in platelets from patients with chronic ITP, suggesting that platelets of chronic ITP may participate in the complicated biological process by means of GPCR-mediated signaling pathways.
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Stelcer E, Milecka P, Komarowska H, Jopek K, Tyczewska M, Szyszka M, Lesniczak M, Suchorska W, Bekova K, Szczepaniak B, Ruchala M, Karczewski M, Wierzbicki T, Szaflarski W, Malendowicz LK, Rucinski M. Adropin Stimulates Proliferation and Inhibits Adrenocortical Steroidogenesis in the Human Adrenal Carcinoma (HAC15) Cell Line. Front Endocrinol (Lausanne) 2020; 11:561370. [PMID: 33133015 PMCID: PMC7579427 DOI: 10.3389/fendo.2020.561370] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 09/04/2020] [Indexed: 12/21/2022] Open
Abstract
Adropin is a multifunctional peptide hormone encoded by the ENHO (energy homeostasis associated) gene. It plays a role in mechanisms related to increased adiposity, insulin resistance, as well as glucose, and lipid metabolism. The low adropin levels are strongly associated with obesity independent insulin resistance. On the other hand, overexpression or exogenous administration of adropin improves glucose homeostasis. The multidirectional, adropin-related effects associated with the regulation of metabolism in humans also appear to be attributable to the effects of this peptide on the activity of various elements of the endocrine system including adrenal cortex. Therefore, the main purpose of the present study was to investigate the effect of adropin on proliferation and secretory activity in the human HAC15 adrenal carcinoma cell line. In this study, we obtained several highly interesting findings. First, GPR19, the main candidate sensitizer of adrenocortical cells to adropin, was expressed in HAC15 cells. Moreover, GPR19 expression was relatively stable and not regulated by ACTH, forskolin, or adropin itself. Our findings also suggest that adropin has the capacity to decrease expression levels of steroidogenic genes such as steroidogenic acute regulatory protein (StAR) and CYP11A1, which then led to a statistically significant inhibition in cortisol and aldosterone biosynthesis and secretion. Based on whole transcriptome study and research involving transforming growth factor (TGF)-β type I receptor kinase inhibitor we demonstrated that attenuation of steroidogenesis caused by adropin is mediated by the TGF-β signaling pathway likely to act through transactivation mechanism. We found that HAC15 cells treated with adropin presented significantly higher proliferation levels than untreated cells. Using specific intracellular inhibitors, we showed that adropin stimulate proliferation via ERK1/2 and AKT dependent signaling pathways. We have also demonstrated that expression of GPR19 is elevated in adrenocortical carcinoma in relation to normal adrenal glands. High level of GPR19 expression in adrenocortical carcinoma may constitute a negative prognostic factor of disease progression.
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Molina L, Bustamante F, Ortloff A, Ramos I, Ehrenfeld P, Figueroa CD. Continuous Exposure of Breast Cancer Cells to Tamoxifen Upregulates GPER-1 and Increases Cell Proliferation. Front Endocrinol (Lausanne) 2020; 11:563165. [PMID: 33117280 PMCID: PMC7561417 DOI: 10.3389/fendo.2020.563165] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 09/08/2020] [Indexed: 12/13/2022] Open
Abstract
GPER-1 is a novel membrane sited G protein-coupled estrogen receptor. Clinical studies have shown that patients suffering an estrogen receptor α (ERα)/GPER-1 positive, breast cancer have a lower survival rate than those who have developed ERα-positive/GPER-1 negative tumors. Moreover, absence of GPER-1 improves the prognosis of patients treated with tamoxifen, the most used selective estrogen receptor modulator to treat ERα-positive breast cancer. MCF-7 breast cancer cells were continuously treated with 1,000 nM tamoxifen for 7 days to investigate its effect on GPER-1 protein expression, cell proliferation and intracellular [Ca2+]i mobilization, a key signaling pathway. Breast cancer cells continuously treated with tamoxifen, exhibited a robust [Ca2+]i mobilization after stimulation with 1,000 nM tamoxifen, a response that was blunted by preincubation of cells with G15, a commercial GPER-1 antagonist. Continuously treated cells also displayed a high [Ca2+]i mobilization in response to a commercial GPER-1 agonist (G1) and to estrogen, in a magnitude that doubled the response observed in untreated cells and was almost completely abolished by G15. Proliferation of cells continuously treated with tamoxifen and stimulated with 2,000 nM tamoxifen, was also higher than that observed in untreated cells in a degree that was approximately 90% attributable to GPER-1. Finally, prolonged tamoxifen treatment did not increase ERα expression, but did overexpress the kinin B1 receptor, another GPCR, which we have previously shown is highly expressed in breast tumors and increases proliferation of breast cancer cells. Although we cannot fully extrapolate the results obtained in vitro to the patients, our results shed some light on the occurrence of drug resistance in breast cancer patients who are ERα/GPER-1 positive, have been treated with tamoxifen and display low survival rate. Overexpression of kinin B1 receptor may explain the increased proliferative response observed in breast tumors under continuous treatment with tamoxifen.
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Gerhart J, Bowers J, Gugerty L, Gerhart C, Martin M, Abdalla F, Bravo-Nuevo A, Sullivan JT, Rimkunas R, Albertus A, Casta L, Getts L, Getts R, George-Weinstein M. Brain-specific angiogenesis inhibitor 1 is expressed in the Myo/Nog cell lineage. PLoS One 2020; 15:e0234792. [PMID: 32614850 PMCID: PMC7332021 DOI: 10.1371/journal.pone.0234792] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/02/2020] [Indexed: 12/14/2022] Open
Abstract
The Myo/Nog cell lineage was discovered in the chick embryo and is also present in adult mammalian tissues. The cells are named for their expression of mRNA for the skeletal muscle specific transcription factor MyoD and bone morphogenetic protein inhibitor Noggin. A third marker for Myo/Nog cells is the cell surface molecule recognized by the G8 monoclonal antibody (mAb). G8 has been used to detect, track, isolate and kill Myo/Nog cells. In this study, we screened a membrane proteome array for the target of the G8 mAb. The array consisted of >5,000 molecules, each synthesized in their native confirmation with appropriate post-translational modifications in a single clone of HEK-293T cells. G8 mAb binding to the clone expressing brain-specific angiogenesis inhibitor 1 (BAI1) was detected by flow cytometry, re-verified by sequencing and validated by transfection with the plasmid construct for BAI1. Further validation of the G8 target was provided by enzyme-linked immunosorbent assay. The G8 epitope was identified by screening a high-throughput, site directed mutagenesis library designed to cover 95–100% of the 954 amino acids of the extracellular domain of the BAI1 protein. The G8 mAb binds within the third thrombospondin repeat of the extracellular domain of human BAI1. Immunofluorescence localization experiments revealed that G8 and a commercially available BAI1 mAb co-localize to the subpopulation of Myo/Nog cells in the skin, eyes and brain. Expression of the multi-functional BAI1 protein in Myo/Nog cells introduces new possibilities for the roles of Myo/Nog cells in normal and diseased tissues.
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Abstract
Proteins are the main source of drug targets and some of them possess therapeutic potential themselves. Among them, membrane proteins constitute approximately 50% of the major drug targets. In the drug discovery pipeline, rapid methods for producing different classes of proteins in a simple manner with high quality are important for structural and functional analysis. Cell-free systems are emerging as an attractive alternative for the production of proteins due to their flexible nature without any cell membrane constraints. In a bioproduction context, open systems based on cell lysates derived from different sources, and with batch-to-batch consistency, have acted as a catalyst for cell-free synthesis of target proteins. Most importantly, proteins can be processed for downstream applications like purification and functional analysis without the necessity of transfection, selection, and expansion of clones. In the last 5 years, there has been an increased availability of new cell-free lysates derived from multiple organisms, and their use for the synthesis of a diverse range of proteins. Despite this progress, major challenges still exist in terms of scalability, cost effectiveness, protein folding, and functionality. In this review, we present an overview of different cell-free systems derived from diverse sources and their application in the production of a wide spectrum of proteins. Further, this article discusses some recent progress in cell-free systems derived from Chinese hamster ovary and Sf21 lysates containing endogenous translocationally active microsomes for the synthesis of membrane proteins. We particularly highlight the usage of internal ribosomal entry site sequences for more efficient protein production, and also the significance of site-specific incorporation of non-canonical amino acids for labeling applications and creation of antibody drug conjugates using cell-free systems. We also discuss strategies to overcome the major challenges involved in commercializing cell-free platforms from a laboratory level for future drug development.
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Wiseman DN, Otchere A, Patel JH, Uddin R, Pollock NL, Routledge SJ, Rothnie AJ, Slack C, Poyner DR, Bill RM, Goddard AD. Expression and purification of recombinant G protein-coupled receptors: A review. Protein Expr Purif 2020; 167:105524. [PMID: 31678667 PMCID: PMC6983937 DOI: 10.1016/j.pep.2019.105524] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 01/15/2023]
Abstract
Given their extensive role in cell signalling, GPCRs are significant drug targets; despite this, many of these receptors have limited or no available prophylaxis. Novel drug design and discovery significantly rely on structure determination, of which GPCRs are typically elusive. Progress has been made thus far to produce sufficient quantity and quality of protein for downstream analysis. As such, this review highlights the systems available for recombinant GPCR expression, with consideration of their advantages and disadvantages, as well as examples of receptors successfully expressed in these systems. Additionally, an overview is given on the use of detergents and the styrene maleic acid (SMA) co-polymer for membrane solubilisation, as well as purification techniques.
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Bugda Gwilt K, González DP, Olliffe N, Oller H, Hoffing R, Puzan M, El Aidy S, Miller GM. Actions of Trace Amines in the Brain-Gut-Microbiome Axis via Trace Amine-Associated Receptor-1 (TAAR1). Cell Mol Neurobiol 2020; 40:191-201. [PMID: 31836967 DOI: 10.1007/s10571-019-00772-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 12/04/2019] [Indexed: 12/13/2022]
Abstract
Trace amines and their primary receptor, Trace Amine-Associated Receptor-1 (TAAR1) are widely studied for their involvement in the pathogenesis of neuropsychiatric disorders despite being found in the gastrointestinal tract at physiological levels. With the emergence of the "brain-gut-microbiome axis," we take the opportunity to review what is known about trace amines in the brain, the defined sources of trace amines in the gut, and emerging understandings on the levels of trace amines in various gastrointestinal disorders. Similarly, we discuss localization of TAAR1 expression in the gut, novel findings that TAAR1 may be implicated in inflammatory bowel diseases, and the reported comorbidities of neuropsychiatric disorders and gastrointestinal disorders. With the emergence of TAAR1 specific compounds as next-generation therapeutics for schizophrenia (Roche) and Parkinson's related psychoses (Sunovion), we hypothesize a therapeutic benefit of these compounds in clinical trials in the brain-gut-microbiome axis, as well as a potential for thoughtful manipulation of the brain-gut-microbiome axis to modulate symptoms of neuropsychiatric disease.
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Kim KM, Jung J. Upregulation of G Protein-Coupled Estrogen Receptor by Chrysin-Nanoparticles Inhibits Tumor Proliferation and Metastasis in Triple Negative Breast Cancer Xenograft Model. Front Endocrinol (Lausanne) 2020; 11:560605. [PMID: 33042020 PMCID: PMC7522162 DOI: 10.3389/fendo.2020.560605] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 08/17/2020] [Indexed: 12/18/2022] Open
Abstract
Triple-negative breast cancer (TNBC) is associated with a high mortality rate among women globally. TNBC shows a high rate of recurrence and distant metastasis. Particularly, the chemotherapy is limited because hormone therapy of breast cancer is ineffective. Thus, an effective chemotherapeutic agent is needed for tumor suppression. Chrysin-nanoparticles (chrysin-NPs) were investigated for their inhibitory effect on a MDA-MB-231-derived xenograft model. To gain insight into the underlying mechanisms, we conducted human matrix metalloproteinase (MMP) array, western blot, and immunohistochemistry analysis. Furthermore, in vivo imaging was used to monitor the chemotherapeutic efficacy of chrysin-NPs in a metastasis mouse model. Chrysin-NPs significantly inhibited the proliferation of MDA-MB-231 cells via the PI3K/JNK pathway and induced cell death through the p53-apoptosis pathway, leading to delayed MDA-MB-231-derived tumor growth. Interestingly, chrysin-NPs significantly induced G protein-coupled estrogen receptor (GPER) expression, which suppresses MMPs and NF-κB expression. Chrysin-NPs acted as effective metastasis inhibitors. Our results suggest that chrysin-NPs may be used as an effective adjuvant formulation to inhibit TNBC progression.
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Loftis JM, Lasarev M, Shi X, Lapidus J, Janowsky A, Hoffman WF, Huckans M. Trace amine-associated receptor gene polymorphism increases drug craving in individuals with methamphetamine dependence. PLoS One 2019; 14:e0220270. [PMID: 31600226 PMCID: PMC6786581 DOI: 10.1371/journal.pone.0220270] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 09/27/2019] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Methamphetamine (MA) is a potent agonist at the trace amine-associated receptor 1 (TAAR1). This study evaluated a common variant (CV) in the human TAAR1 gene, synonymous single nucleotide polymorphism (SNP) V288V, to determine the involvement of TAAR1 in MA dependence. METHODS Participants (n = 106) with active MA dependence (MA-ACT), in remission from MA dependence (MA-REM), with active polysubstance dependence, in remission from polysubstance dependence, and with no history of substance dependence completed neuropsychiatric symptom questionnaires and provided blood samples. In vitro expression and function of CV and wild type TAAR1 receptors were also measured. RESULTS The V288V polymorphism demonstrated a 40% increase in TAAR1 protein expression in cell culture, but message sequence and protein function were unchanged, suggesting an increase in translation efficiency. Principal components analysis resolved neuropsychiatric symptoms into four components, PC1 (depression, anxiety, memory, and fatigue), PC2 (pain), PC3 (drug and alcohol craving), and PC4 (sleep disturbances). Analyses of study group and TAAR1 genotype revealed a significant interaction for PC3 (craving response) (p = 0.003). The control group showed no difference in PC3 associated with TAAR1, while adjusted mean craving for the MA-ACT and MA-REM groups, among those with at least one copy of V288V, was estimated to be, respectively, 1.55 (p = 0.036) and 1.77 (p = 0.071) times the adjusted mean craving for those without the TAAR1 SNP. CONCLUSIONS Neuroadaptation to chronic MA use may be altered by TAAR1 genotype and result in increased dopamine signaling and craving in individuals with the V288V genotype.
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Jiang M, Ma X, Zhao Q, Li Y, Xing Y, Deng Q, Shen Y. The neuroprotective effects of novel estrogen receptor GPER1 in mouse retinal ganglion cell degeneration. Exp Eye Res 2019; 189:107826. [PMID: 31586450 DOI: 10.1016/j.exer.2019.107826] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/15/2019] [Accepted: 10/01/2019] [Indexed: 01/09/2023]
Abstract
PURPOSE To investigate the potential protective effect of novel G protein coupled estrogen receptor (GPER1) against the neurotoxicity induced by NMDA in the mouse retina. METHODS We induce retinal ganglion cells (RGCs) toxic injury through intravitreal injection of NMDA or acute ocular hypertension (AOH) induced by anterior chamber infusion with saline. Endogenous ligand 17-β-estradiol (E2), GPER1 agonist (G-1), and E2 with GPER1 antagonist (G-15) or classic estrogen receptor α and β (ERα and ERβ) antagonist tamoxifen (TAM) were subcutaneous administered before NMDA to identify the possible involved receptors. Immunofluorescence staining was performed to explore the survival of RGCs and Müller cell gliosis. TUNEL staining was used to evaluate the RGC apoptosis. The involved molecular pathway was detected via antibody array expression profiling. RESULTS Activation of estrogen receptor by E2 or G-1 could significantly rescue the RGCs injury in NMDA administration. The protective effect was carried exclusively by GPER1 activation. E2 application can still mimicked the protective function when estrogen receptor α and β (ERα and ERβ) blocked by tamoxifen (TAM), while the effects was blocked by GPER1 antagonist G-15. Moreover, the TUNEL positive RGCs and GFAP expression level were both attenuated in G-1 application and the effects could be reversed by G-15. In addition, application of the PI3K/Akt antagonist LY294002 counteracted the effect of G-1. And a number of apoptosis regulatory factors decreased dramatically in the G-1 group, including Bad, Caspase 3, Caspase 7, Smad2, P-53 and TAK1. Also, similar protective effect of G-1 was spotted in acute ocular hypertension (AOH) model. CONCLUSION Estrogen played a protective role via a novel estrogen receptor, GPER1, instead of classical receptors ERα or ERβ. Activation of GPER1 attenuated RGCs apoptosis and Müller cells gliosis, indicating GPER1 as a potential treatment target in RGCs degeneration diseases.
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Insel PA, Sriram K, Gorr MW, Wiley SZ, Michkov A, Salmerón C, Chinn AM. GPCRomics: An Approach to Discover GPCR Drug Targets. Trends Pharmacol Sci 2019; 40:378-387. [PMID: 31078319 PMCID: PMC6604616 DOI: 10.1016/j.tips.2019.04.001] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 03/17/2019] [Accepted: 04/03/2019] [Indexed: 01/14/2023]
Abstract
G protein-coupled receptors (GPCRs) are targets for ∼35% of approved drugs but only ∼15% of the ∼800 human GPCRs are currently such targets. GPCRomics, the use of unbiased, hypothesis-generating methods [e.g., RNA-sequencing (RNA-seq)], with tissues and cell types to identify and quantify GPCR expression, has led to the discovery of previously unrecognized GPCRs that contribute to functional responses and pathophysiology and that may be therapeutic targets. The combination of GPCR expression data with validation studies (e.g., signaling and functional activities) provides opportunities for the discovery of disease-relevant GPCR targets and therapeutics. Here, we review insights from GPCRomic approaches, gaps in knowledge, and future directions by which GPCRomics can advance GPCR biology and the discovery of new GPCR-targeted drugs.
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Giulianelli R, Nardoni S, Bruzzese D, Falavolti C, Mirabile G, Bellangino M, Tema G, Gentile BC, Albanesi L, Buscarini M, Tariciotti P, Lombardo R. Urotensin II receptor expression in prostate cancer patients: A new possible marker. Prostate 2019; 79:288-294. [PMID: 30411388 DOI: 10.1002/pros.23734] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/09/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND Urotensin II receptor has been poorly studied in prostate cancer. To evaluate the expression of urotensin II receptor (UII-R) in patients undergoing radical prostatectomy. METHODS Overall, we identified 140 patients treated with retropubic radical prostatectomy (RP) in one center. UII-R was evaluated in prostate biopsies with immunohistochemical staining, resulting in a granular cytoplasmic positivity, through automated system using the kit Urotensin II Receptor Detection System provided by Pharmabullet srl. Immunostained slides were independently and blindly evaluated by ten uro-pathologists. To evaluate UTII-R expression three different parameters were considered: localization, granules dimensions and intensity of expression. A score from 0 to 3 was applied to each parameter to obtain a score from 0 to 9. Each parameter and the total score were evaluated as predictors of high grade disease on surgical pathology and of advanced stage disease. Accuracy of total score for the prediction of upgrading and upstaging was analyzed using receiver operator characteristics curve and decision curve analysis (DCA). RESULTS On radical prostatectomy 92/140 (66%) presented high grade disease on surgical pathology. Patients with high grade disease presented an apical distribution of the receptor, larger granules and a more intense expression when compared to patients with low grade disease. A well they presented a higher total score. Subscores and total scores were found to be predictors of upgrading and upstaging. On ROC analysis total score presented an AUC of 0.72 and 0.70, respectively, for the prediction of upgrading and upstaging. On DCA total score showed a clinical benefit in the prediction of adverse pathological outcomes. CONCLUSION Urotensin II receptor is a potential marker of adverse pathological outcomes. Further studies should confirm our data and evaluate its role as a prognostic marker.
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Rudenko O, Shang J, Munk A, Ekberg JP, Petersen N, Engelstoft MS, Egerod KL, Hjorth SA, Wu M, Feng Y, Zhou YP, Mokrosinski J, Thams P, Reimann F, Gribble F, Rehfeld JF, Holst JJ, Treebak JT, Howard AD, Schwartz TW. The aromatic amino acid sensor GPR142 controls metabolism through balanced regulation of pancreatic and gut hormones. Mol Metab 2019; 19:49-64. [PMID: 30472415 PMCID: PMC6323244 DOI: 10.1016/j.molmet.2018.10.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 10/29/2018] [Accepted: 10/31/2018] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES GPR142, which is highly expressed in pancreatic islets, has recently been deorphanized as a receptor for aromatic amino acids; however, its physiological role and pharmacological potential is unclear. METHODS AND RESULTS We find that GPR142 is expressed not only in β- but also in α-cells of the islets as well as in enteroendocrine cells, and we confirm that GPR142 is a highly selective sensor of essential aromatic amino acids, in particular Trp and oligopeptides with N-terminal Trp. GPR142 knock-out mice displayed a very limited metabolic phenotype but demonstrated that L-Trp induced secretion of pancreatic and gut hormones is mediated through GPR142 but that the receptor is not required for protein-induced hormone secretion. A synthetic GPR142 agonist stimulated insulin and glucagon as well as GIP, CCK, and GLP-1 secretion. In particular, GIP secretion was sensitive to oral administration of the GPR142 agonist an effect which in contrast to the other hormones was blocked by protein load. Oral administration of the GPR142 agonist increased [3H]-2-deoxyglucose uptake in muscle and fat depots mediated through insulin action while it lowered liver glycogen conceivably mediated through glucagon, and, consequently, it did not lower total blood glucose. Nevertheless, acute administration of the GPR142 agonist strongly improved oral glucose tolerance in both lean and obese mice as well as Zucker fatty rat. Six weeks in-feed chronic treatment with the GPR142 agonist did not affect body weight in DIO mice, but increased energy expenditure and carbohydrate utilization, lowered basal glucose, and improved insulin sensitivity. CONCLUSIONS GPR142 functions as a sensor of aromatic amino acids, controlling GIP but also CCK and GLP-1 as well as insulin and glucagon in the pancreas. GPR142 agonists could have novel interesting potential in modifying metabolism through a balanced action of gut hormones as well as both insulin and glucagon.
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Zhu X, Huang G, Jin P. Clinicopathological and prognostic significance of aberrant G protein-couple receptor 110 (GPR110) expression in gastric cancer. Pathol Res Pract 2018; 215:539-545. [PMID: 30638950 DOI: 10.1016/j.prp.2018.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 11/13/2018] [Accepted: 12/05/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND GPR110 is a member of the adhesion G protein-coupled receptor family, which has been identified as an oncogene in various cancers, including hepatocellular carcinoma, lung cancer, prostatic cancer and glioma. Whereas the expression and the clinical relevance of GPR110 in gastric cancer has not been investigated. The research purpose of this study was to explore the expression pattern of GPR110 and evaluate its clinical-pathological and prognostic value in gastric cancer. METHODS In this study, the expression of GPR110 was detected in 117 paired gastric cancer tissues and adjacent non-tumorous tissues by using qRT-PCR and immunohistochemical assays. Univariate Kaplan-Meier and multivariate Cox analysis were used to determine the prognostic value of GPR110 in GC. RESULTS We demonstrated that the mRNA and protein levels of GPR110 in GC tissues were overexpressed than the adjacent non-tumorous tissues. Furthermore, elevated GPR110 protein expression was correlated with decreased overall and recurrence-free survival (P = 0.001 and P = 0.000, respectively). Univariate and multivariate analysis indicated that GPR110 protein level may serve as an independent prognostic indicator for determining prognosis of GC patients. CONCLUSIONS Our study revealed that high expression of GPR110 predicts the poor prognosis of GC patients, and GPTR110 may function as a potential biomarker for the diagnosis of GC.
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Ignatov T, Claus M, Nass N, Haybaeck J, Seifert B, Kalinski T, Ortmann O, Ignatov A. G-protein-coupled estrogen receptor GPER-1 expression in hormone receptor-positive breast cancer is associated with poor benefit of tamoxifen. Breast Cancer Res Treat 2018; 174:121-127. [PMID: 30478785 DOI: 10.1007/s10549-018-5064-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 11/17/2018] [Indexed: 02/01/2023]
Abstract
BACKGROUND The role of G-protein-coupled estrogen receptor 1 (GPER-1) in the development of tamoxifen resistance in breast cancer is a highly controversial issue. The aim of this study was to determine the expression of GPER-1 in the clinical routine under conditions of endocrine treatment. PATIENTS AND METHODS GPER-1 expression was analyzed in 442 patients with primary invasive breast cancer. GPER-1 score of > 3 was determined as positive. Expression data were correlated with clinical and pathological characteristics and patient survival. RESULTS GPER-1 expression was observed in 352 (80.9%) cases, and positively correlated with estrogen and progesterone receptor status (p = 0.0001). GPER-1 positivity was associated with an increased grade of differentiation (p = 0.0001) and with a low level of Ki-67 expression (p = 0.0001). High GPER-1 expression was associated with a decreased level upon systemic treatment (p = 0.011). In the whole cohort, GPER-1 expression was associated with prolonged disease-free survival (DFS). DFS between tamoxifen- and aromatase inhibitor-treated GPER-1-positive patients was similar (p = 0.090). Notably, after matching the analysis for the most important prognostic factors, DFS for tamoxifen-treated GPER-1-positive patients was 69.1%, which is a percentage that is significantly lower compared to DFS for GPER-1-positive patients treated with aromatase inhibitors (92.7%) (p = 0.005). CONCLUSION GPER-1 expression is a favorable prognostic factor in breast cancer patients. Its predictive role for poor benefit form tamoxifen treatment should be investigated in further studies.
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Liu C, Yang CX, Chen XR, Liu BX, Li Y, Wang XZ, Sun W, Li P, Kong XQ. Alamandine attenuates hypertension and cardiac hypertrophy in hypertensive rats. Amino Acids 2018; 50:1071-1081. [PMID: 29752563 PMCID: PMC6060955 DOI: 10.1007/s00726-018-2583-x] [Citation(s) in RCA: 52] [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: 03/21/2018] [Accepted: 04/27/2018] [Indexed: 12/21/2022]
Abstract
Oral administration of the peptide alamandine has antihypertensive and anti-fibrotic effects in rats. This work aimed to determine whether subcutaneous alamandine injection would attenuate hypertension and cardiac hypertrophy, and improve the function of a major target of hypertension-related damage, the left ventricle (LV), in spontaneously hypertensive rats (SHRs). This was examined in vivo in SHRs and normotensive rats subjected to 6-week subcutaneous infusion of alamandine or saline control, and in vitro in H9C2-derived and primary neonatal rat cardiomyocytes treated with angiotensin (Ang) II to model cardiac hypertrophy. Tail artery blood pressure measurement and transthoracic echocardiography showed that hypertension and impaired LV function in SHRs were ameliorated upon alamandine infusion. Alamandine administration also decreased the mass gains of heart and lung in SHRs, suppressed cardiomyocyte cross-sectional area expansion, and inhibited the mRNA levels of atrial natriuretic peptide and brain natriuretic peptide. The expression of alamandine receptor Mas-related G protein-coupled receptor, member D was increased in SHR hearts and in cardiomyocytes treated with Ang II. Alamandine inhibited the increases of protein kinase A (PKA) levels in the heart in SHRs and in cardiomyocytes treated with Ang II. In conclusion, the present study showed that alamandine administration attenuates hypertension, alleviates cardiac hypertrophy, and improves LV function. PKA signaling may be involved in the mechanisms underlying these effects.
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Suzuki K, Murano T, Shimizu H, Ito G, Nakata T, Fujii S, Ishibashi F, Kawamoto A, Anzai S, Kuno R, Kuwabara K, Takahashi J, Hama M, Nagata S, Hiraguri Y, Takenaka K, Yui S, Tsuchiya K, Nakamura T, Ohtsuka K, Watanabe M, Okamoto R. Single cell analysis of Crohn's disease patient-derived small intestinal organoids reveals disease activity-dependent modification of stem cell properties. J Gastroenterol 2018; 53:1035-1047. [PMID: 29374777 PMCID: PMC6132922 DOI: 10.1007/s00535-018-1437-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 01/21/2018] [Indexed: 02/04/2023]
Abstract
BACKGROUND Intestinal stem cells (ISCs) play indispensable roles in the maintenance of homeostasis, and also in the regeneration of the damaged intestinal epithelia. However, whether the inflammatory environment of Crohn's disease (CD) affects properties of resident small intestinal stem cells remain uncertain. METHODS CD patient-derived small intestinal organoids were established from enteroscopic biopsy specimens taken from active lesions (aCD-SIO), or from mucosa under remission (rCD-SIO). Expression of ISC-marker genes in those organoids was examined by immunohistochemistry, and also by microfluid-based single-cell multiplex gene expression analysis. The ISC-specific function of organoid cells was evaluated using a single-cell organoid reformation assay. RESULTS ISC-marker genes, OLFM4 and SLC12A2, were expressed by an increased number of small intestinal epithelial cells in the active lesion of CD. aCD-SIOs, rCD-SIOs or those of non-IBD controls (NI-SIOs) were successfully established from 9 patients. Immunohistochemistry showed a comparable level of OLFM4 and SLC12A2 expression in all organoids. Single-cell gene expression data of 12 ISC-markers were acquired from a total of 1215 cells. t-distributed stochastic neighbor embedding analysis identified clusters of candidate ISCs, and also revealed a distinct expression pattern of SMOC2 and LGR5 in ISC-cluster classified cells derived from aCD-SIOs. Single-cell organoid reformation assays showed significantly higher reformation efficiency by the cells of the aCD-SIOs compared with that of cells from NI-SIOs. CONCLUSIONS aCD-SIOs harbor ISCs with modified marker expression profiles, and also with high organoid reformation ability. Results suggest modification of small intestinal stem cell properties by unidentified factors in the inflammatory environment of CD.
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Fujimoto J, Nunomura-Nakamura S, Liu Y, Lang W, McDowell T, Jakubek Y, Ezzeddine D, Ochieng JK, Petersen J, Davies G, Fukuoka J, Wistuba II, Ehli E, Fowler J, Scheet P, Kadara H. Development of Kras mutant lung adenocarcinoma in mice with knockout of the airway lineage-specific gene Gprc5a. Int J Cancer 2017; 141:1589-1599. [PMID: 28653505 PMCID: PMC5774849 DOI: 10.1002/ijc.30851] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/19/2017] [Accepted: 06/16/2017] [Indexed: 12/15/2022]
Abstract
Despite the urgency for prevention and treatment of lung adenocarcinoma (LUAD), we still do not know drivers in pathogenesis of the disease. Earlier work revealed that mice with knockout of the G-protein coupled receptor Gprc5a develop late onset lung tumors including LUADs. Here, we sought to further probe the impact of Gprc5a expression on LUAD pathogenesis. We first surveyed GPRC5A expression in human tissues and found that GPRC5A was markedly elevated in human normal lung relative to other normal tissues and was consistently downregulated in LUADs. In sharp contrast to wild-type littermates, Gprc5a-/- mice treated chronically with the nicotine-specific carcinogen NNK developed LUADs by 6 months following NNK exposure. Immunofluorescence analysis revealed that the LUADs exhibited abundant expression of surfactant protein C and lacked the clara cell marker Ccsp, suggesting that these LUADs originated from alveolar type II cells. Next, we sought to survey genome-wide alterations in the pathogenesis of Gprc5a-/- LUADs. Using whole exome sequencing, we found that carcinogen-induced LUADs exhibited markedly higher somatic mutation burdens relative to spontaneous tumors. All LUADs were found to harbor somatic mutations in the Kras oncogene (p. G12D or p. Q61R). In contrast to spontaneous lesions, carcinogen-induced Gprc5a-/- LUADs exhibited mutations (variants and copy number gains) in additional drivers (Atm, Kmt2d, Nf1, Trp53, Met, Ezh2). Our study underscores genomic alterations that represent early events in the development of Kras mutant LUAD following Gprc5a loss and tobacco carcinogen exposure and that may constitute targets for prevention and early treatment of this disease.
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Mashanov V, Zueva O, Mashanova D, García-Arrarás JE. Expression of stem cell factors in the adult sea cucumber digestive tube. Cell Tissue Res 2017; 370:427-440. [PMID: 28986650 DOI: 10.1007/s00441-017-2692-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/30/2017] [Indexed: 01/26/2023]
Abstract
Homeostatic cell turnover has been extensively characterized in mammals. In their adult tissues, lost or aging differentiated cells are replenished by a self-renewing cohort of stem cells. The stem cells have been particularly well studied in the intestine and are clearly identified by the expression of marker genes including Lgr5 and Bmi1. It is, however, unknown if the established principles of tissue renewal learned from mammals would be operating in non-mammalian systems. Here, we study homeostatic cell turnover in the sea cucumber digestive tube, the organ with high tissue plasticity even in adult animals. Both the luminal epithelium and mesothelium express orthologs of mammalian Lgr5 and Bmi1. However, unlike in mammals, there is no segregation of these positively labeled cells to specific regions in the luminal epithelium, where most of the cell proliferation would take place. In the mesothelium, the cells expressing the stem cell markers are tentatively identified as peritoneocytes. There are significant differences among the five anatomical gut regions in cell renewal dynamics and stem factor expression. The cloaca differs from the rest of the digestive tube as the region with the highest expression of the Lgr5 ortholog, lowest level of Bmi1 and the longest retention of BrdU-labeled cells.
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Bonfanti E, Gelosa P, Fumagalli M, Dimou L, Viganò F, Tremoli E, Cimino M, Sironi L, Abbracchio MP. The role of oligodendrocyte precursor cells expressing the GPR17 receptor in brain remodeling after stroke. Cell Death Dis 2017; 8:e2871. [PMID: 28594400 PMCID: PMC5520912 DOI: 10.1038/cddis.2017.256] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/23/2017] [Accepted: 04/10/2017] [Indexed: 01/26/2023]
Abstract
Following stroke-induced neuronal damage, quiescent oligodendrocyte precursors (OPCs) are activated to proliferate and later to differentiate to myelin-producing cells. GPR17, a receptor transiently expressed on early OPCs, has emerged as a target to implement stroke repair through stimulation of OPC maturation. However, being GPR17 completely downregulated in myelin-producing oligodendrocytes, its actual role in determining the final fate of OPCs after cerebral ischemia is still uncertain. Here, to univocally define the spatiotemporal changes and final fate of GPR17-expressing OPCs, we induced ischemia by middle cerebral artery occlusion (MCAo) in reporter GPR17iCreERT2:CAG-eGreen florescent protein (GFP) mice, in which, upon tamoxifen treatment, cells expressing GPR17 become green and traceable for their entire life. Starting from 3 days and up to 2 weeks after MCAo, GFP+ cells markedly accumulated in regions surrounding the ischemic lesion; several of them proliferated, as shown by co-labeling of the DNA synthesis marker 5-Bromo-2'-deoxyuridine (BrdU). Almost all GFP+/BrdU+ cells expressed the OPC early marker neural/glial antigen 2 (NG2), indicating that they were still precursors. Accumulation of GFP+ cells was also because of OPC recruitment from surrounding areas, as suggested in vivo by acquisition of typical features of migrating OPCs, shown in vitro in presence of the chemoattractant PDGF-AA and confirmed by transplantation of GFP+-OPCs in wild-type MCAo mice. Eight weeks after MCAo, only some of these precociously recruited cells had undergone maturation as shown by NG2 loss and acquisition of mature myelinating markers like GSTpi. A pool of recruited GFP+-OPCs was kept at a precursor stage to likely make it available for further insults. Thus, very early after ischemia, GFP+-OPCs proliferate and migrate toward the lesion; however, most of these cells remain undifferentiated, suggesting functional roles other than myelination.
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Dragano NRV, Solon C, Ramalho AF, de Moura RF, Razolli DS, Christiansen E, Azevedo C, Ulven T, Velloso LA. Polyunsaturated fatty acid receptors, GPR40 and GPR120, are expressed in the hypothalamus and control energy homeostasis and inflammation. J Neuroinflammation 2017; 14:91. [PMID: 28446241 PMCID: PMC5405534 DOI: 10.1186/s12974-017-0869-7] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 04/20/2017] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The consumption of large amounts of dietary fats is one of the most important environmental factors contributing to the development of obesity and metabolic disorders. GPR120 and GPR40 are polyunsaturated fatty acid receptors that exert a number of systemic effects that are beneficial for metabolic and inflammatory diseases. Here, we evaluate the expression and potential role of hypothalamic GPR120 and GPR40 as targets for the treatment of obesity. METHODS Male Swiss (6-weeks old), were fed with a high fat diet (HFD, 60% of kcal from fat) for 4 weeks. Next, mice underwent stereotaxic surgery to place an indwelling cannula into the right lateral ventricle. intracerebroventricular (icv)-cannulated mice were treated twice a day for 6 days with 2.0 μL saline or GPR40 and GPR120 agonists: GW9508, TUG1197, or TUG905 (2.0 μL, 1.0 mM). Food intake and body mass were measured during the treatment period. At the end of the experiment, the hypothalamus was collected for real-time PCR analysis. RESULTS We show that both receptors are expressed in the hypothalamus; GPR120 is primarily present in microglia, whereas GPR40 is expressed in neurons. Upon intracerebroventricular treatment, GW9508, a non-specific agonist for both receptors, reduced energy efficiency and the expression of inflammatory genes in the hypothalamus. Reducing GPR120 hypothalamic expression using a lentivirus-based approach resulted in the loss of the anti-inflammatory effect of GW9508 and increased energy efficiency. Intracerebroventricular treatment with the GPR120- and GPR40-specific agonists TUG1197 and TUG905, respectively, resulted in milder effects than those produced by GW9508. CONCLUSIONS GPR120 and GPR40 act in concert in the hypothalamus to reduce energy efficiency and regulate the inflammation associated with obesity. The combined activation of both receptors in the hypothalamus results in better metabolic outcomes than the isolated activation of either receptor alone.
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Muñoz-Sánchez MÁ, Rodríguez-Rodríguez A, Egea-Guerrero JJ, Gordillo-Escobar E, Vilches-Arenas Á, Carrillo-Vico A, Guerrero JM, Murillo-Cabezas F. Urotensinergic system genes in experimental subarachnoid hemorrhage. Med Intensiva 2017; 41:468-474. [PMID: 28081921 DOI: 10.1016/j.medin.2016.10.013] [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: 06/17/2016] [Revised: 10/14/2016] [Accepted: 10/23/2016] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Cerebral vasospasm, one of the main complications of subarachnoid hemorrhage (SAH), is characterized by arterial constriction and mainly occurs from day 4 until the second week after the event. Urotensin-II (U-II) has been described as the most potent vasoconstrictor peptide in mammals. An analysis is made of the serum U-II concentrations and mRNA expression levels of U-II, urotensin related peptide (URP) and urotensin receptor (UT) genes in an experimental murine model of SAH. DESIGN An experimental study was carried out. SETTING Experimental operating room of the Biomedicine Institute of Seville (IBiS), Virgen del Rocío University Hospital (Seville, Spain). PARTICIPANTS 96 Wistar rats: 74 SAH and 22 sham intervention animals. INTERVENTIONS Day 1: blood sampling, followed by the percutaneous injection of 100μl saline (sham) or blood (SAH) into the subarachnoid space. Day 5: blood sampling, followed by sacrifice of the animals. MAIN VARIABLES OF INTEREST Weight, early mortality, serum U-II levels, mRNA values for U-II, URP and UT. RESULTS Serum U-II levels increased in the SAH group from day 1 (0.62pg/mL [IQR 0.36-1.08]) to day 5 (0.74pg/mL [IQR 0.39-1.43]) (p<0.05), though not in the sham group (0.56pg/mL [IQR 0.06-0.83] day 1; 0.37pg/mL [IQR 0.23-0.62] day 5; p=0.959). Between-group differences were found on day 5 (p<0.05). The ROC analysis showed that the day 5 serum U-II levels (AUC=0.691), URP mRNA (AUC=0.706) and UT mRNA (AUC=0.713) could discriminate between sham and SAH rats. The normal serum U-II concentration range in rats was 0.56pg/mL (IQR 0.06-0.83). CONCLUSION The urotensinergic system is upregulated on day 5 in an experimental model of SAH.
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MESH Headings
- Animals
- Biomarkers
- Disease Models, Animal
- Gene Expression Regulation
- Peptide Hormones/biosynthesis
- Peptide Hormones/blood
- Peptide Hormones/genetics
- RNA, Messenger/biosynthesis
- RNA, Messenger/blood
- RNA, Messenger/genetics
- ROC Curve
- Rats
- Rats, Wistar
- Real-Time Polymerase Chain Reaction
- Receptors, G-Protein-Coupled/biosynthesis
- Receptors, G-Protein-Coupled/blood
- Receptors, G-Protein-Coupled/genetics
- Sensitivity and Specificity
- Subarachnoid Hemorrhage/complications
- Subarachnoid Hemorrhage/genetics
- Urotensins/biosynthesis
- Urotensins/blood
- Urotensins/genetics
- Vasoconstriction/genetics
- Vasospasm, Intracranial/etiology
- Vasospasm, Intracranial/genetics
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