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See detailA dynamic and screening-compatible nanoluciferase-based complementation assay enables profiling of individual GPCR-G protein interactions
Laschet, Céline ULiege; Dupuis, Nadine; Hanson, Julien ULiege

in Journal of Biological Chemistry (2019), 294(11), 4079-4090

G protein-coupled receptors (GPCRs) are currently the target of more than 30% of the marketed medicines. However, there is an important medical need for ligands with improved pharmacological activities on ... [more ▼]

G protein-coupled receptors (GPCRs) are currently the target of more than 30% of the marketed medicines. However, there is an important medical need for ligands with improved pharmacological activities on validated drug targets. Moreover, most of these ligands remain poorly characterized, notably because of a lack of pharmacological tools. Thus, there is an important demand for innovative assays that can detect and drive the design of compounds with novel or improved pharmacological properties. In particular, a functional and screening-compatible GPCR-G protein interaction assay is still unavailable. Here, we report on a nanoluciferase-based complementation technique to detect ligands that promote a GPCR-G protein interaction. We demonstrate that our system can be used to profile compounds with regard to the G proteins they activate through a given GPCR. Furthermore, we established a proof of applicability of screening for distinct G proteins on dopamine receptor D2 whose differential coupling to Gαi/o family members has been extensively studied. In a D2-Gαi1 versus D2- Gαo screening, we retrieved five agonists that are currently being used in antiparkinsonian medications. We determined that in this assay, piribedil and pergolide are full agonists for the recruitment of Gαi1 but are partial agonists for Gαo, that the agonist activity of ropinirole is biased in favor of Gαi1 recruitment, and that the agonist activity of apomorphine is biased for Gαo. We proposed that this newly developed assay could be used to develop molecules that selectively modulate a particular G protein pathway. [less ▲]

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See detailThe causes and consequences of pituitary gigantism
Beckers, Albert ULiege; PETROSSIANS, Patrick ULiege; Hanson, Julien ULiege et al

in Nature Reviews. Endocrinology (2018), 14

In the general population, height is determined by a complex interplay between genetic and environmental factors. Pituitary gigantism is a rare but very important subgroup of patients with excessive ... [more ▼]

In the general population, height is determined by a complex interplay between genetic and environmental factors. Pituitary gigantism is a rare but very important subgroup of patients with excessive height, as it has an identifiable and clinically treatable cause. The disease is caused by chronic growth hormone and insulin-like growth factor 1 secretion from a pituitary somatotrope adenoma that forms before the closure of the epiphyses. If not controlled effectively, this hormonal hypersecretion could lead to extremely elevated final adult height. The past 10 years have seen marked advances in the understanding of pituitary gigantism, including the identification of genetic causes in \~50\% of cases, such as mutations in the AIP gene or chromosome Xq26.3 duplications in X-linked acrogigantism syndrome. Pituitary gigantism has a male preponderance, and patients usually have large pituitary adenomas. The large tumour size, together with the young age of patients and frequent resistance to medical therapy, makes the management of pituitary gigantism complex. Early diagnosis and rapid referral for effective therapy appear to improve outcomes in patients with pituitary gigantism; therefore, a high level of clinical suspicion and efficient use of diagnostic resources is key to controlling overgrowth and preventing patients from reaching very elevated final adult heights. [less ▲]

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See detailPartial filling capillary electrophoretic mobility shift competition assay: a versatile and reliable tool for the assessment of weak biomolecular interactions
Farcas, Elena ULiege; Servais, Anne-Catherine ULiege; Hanson, Julien ULiege et al

Conference (2018, September 10)

Fragment-based drug discovery (FBDD) proved its efficacy in the past 20 years, due to its ability to perform efficient and fruitful optimization campaigns, and is now a well recognized strategy for both ... [more ▼]

Fragment-based drug discovery (FBDD) proved its efficacy in the past 20 years, due to its ability to perform efficient and fruitful optimization campaigns, and is now a well recognized strategy for both academia and pharmaceutical industry. FBDD detects low molecular-weight (MW) ligands (fragments) that bind to biologically important targets, then a structure-guided fragment growing or merging approach is performed giving rise to potent molecules with drug-like properties. However, the analytical arsenal able to point out weak interactions is rather expensive, time consuming or unable to reflect the physiological environment. In this framework, we developed a generic, fully automated, microscale electrophoretic mobility shift competition assay that can be used for primary screening of weak biomolecular interactions between fragments and the target of interest. The affinity capillary electrophoresis (ACE) competitive approach is based on the monitoring of the competition of fragments with a known target inhibitor (PL) for the same active site. The consequence of the competition is a modification of PL electrophoretic mobility, modification that can be measured and used for ligand screening and/or IC50 determination. To achieve our goal, particular attention has been paid to the optimization of the binding environment parameters: an optimal buffer was used for the binding measurements, a partial filling approach was considered to gain sensitivity and to reduce protein consumption and a neutral dynamic coating was performed to reduce protein adsorption to the capillary wall. Moreover, the binding partners concentrations and the electrophoretic conditions were carefully optimized. It is noteworthy that the interactions occur in solution, using the protein in its native form, thus mimicking the physiological environment.The accuracy and reliability of the proposed method was demonstrated by monitoring the competition of two known fragments inhibiting thrombin, namely benzamidine and p-aminobenzamidine and a relatively weak inhibitor, nafamostat with a known thrombin inhibitor, pefabloc (PEFA). The measured IC50 were found to be in good accordance with the previously reported ones. Additionally, a small chemical library was built to evaluate the performance of the newly developed screening-bioassay. The optimized method proved to be remarkably reproducible (migration time RSDs < 1.2%) and selective. The results prove the high discriminatory potency of the method and its ability to screen neutral, negatively or positively charged molecules, as well as molecules that have no or low UV-VIS absorbance, significantly expanding the applicability of the assay compared to a direct approach [1]. Finally, the ability of this approach to discriminate between competitive and irreversible thrombin binders was also demonstrated.References [1] E. Farcas, C. Bouckaert, A.-C. Servais, J. Hanson, L. Pochet, M. Fillet, Analytica Chimica Acta, 2017, 984, 211-222 [less ▲]

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See detailGPR101 orphan receptor: a novel cause of growth hormone deregulation
Abboud, Dayana ULiege; Daly, Adrian ULiege; Laschet, Céline ULiege et al

Conference (2018, July 05)

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See detailThe G Protein-Coupled Receptors Deorphanization Landscape
Laschet, Céline ULiege; Dupuis, Nadine; Hanson, Julien ULiege

in Biochemical Pharmacology (2018), 153

G protein-coupled receptors (GPCRs) are usually highlighted as being both the largest family of membrane proteins and the most productive source of drug targets. However, most of the GPCRs are ... [more ▼]

G protein-coupled receptors (GPCRs) are usually highlighted as being both the largest family of membrane proteins and the most productive source of drug targets. However, most of the GPCRs are understudied and hence cannot be used immediately for innovative therapeutic strategies. Besides, there are still around 100 orphan receptors, with no described endogenous ligand and no clearly defined function. The race to discover new ligands for these elusive receptors seems to be less intense than before. Here, we present an update of the various strategies employed to assign a function to these receptors and to discover new ligands. We focus on the recent advances in the identification of endogenous ligands with a detailed description of newly deorphanized receptors. Replication being a key parameter in these endeavors, we also discuss the latest controversies about problematic ligand-receptor pairings. In this context, we propose several recommendations in order to strengthen the reporting of new ligand-receptor pairs. [less ▲]

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See detailAtypical Ligand Binding and Activation Modes of ACKR3/CXCR7
Meyrath, Max Marc Roger ULiege; Szpakowska, Martyna; Reynders, Nathan et al

Speech/Talk (2018)

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike ... [more ▼]

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike classical chemokine receptors, can respond to chemokines from both the CXC and CC families as well as to the endogenous peptides BAM22 and adrenomedullin. Moreover, despite belonging to the G protein coupled receptor family, its function appears to be mainly dependent on β-arrestin. ACKR3 has also been shown to continuously cycle between the plasma membrane and the endosomal compartments, suggesting a possible role as a scavenging receptor. So far, the molecular basis accounting for these atypical binding and signalling properties remains elusive. Noteworthy, ACKR3 extracellular domains bear three disulphide bridges. Two of them lie on top of the two main binding subpockets and are conserved among chemokine receptors, and one, specific to ACKR3, forms an intra-N terminus four-residue-loop of so far unknown function. Here, by mutational and functional studies, we examined the impact of the different disulphide bridges for ACKR3 folding, ligand binding and activation. We showed that, in contrast to most classical chemokine receptors, none of the extracellular disulphide bridges was essential for ACKR3 function. However, the disruption of the unique ACKR3 N-terminal loop drastically reduced the binding of CC chemokines whereas it only had a mild impact on CXC chemokine binding. Mutagenesis also uncovered that chemokine and endogenous non-chemokine ligands interact and activate ACKR3 according to distinct binding modes characterized by different transmembrane domain subpocket occupancy and N-terminal loop contribution, with BAM22 mimicking the binding mode of CC chemokine N terminus. [less ▲]

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See detailDistinct binding and activation modes of the atypical chemokine receptor ACKR3/CXCR7 by chemokine and endogenous non-chemokine agonists
Meyrath, Max Marc Roger ULiege; Szpakowska, Martyna; Reynders, Nathan et al

Poster (2018, May 28)

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike ... [more ▼]

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike classical chemokine receptors, can respond to chemokines from both the CXC and CC families as well as to the endogenous peptides BAM22 and adrenomedullin. Moreover, despite belonging to the G protein coupled receptor family, its function appears to be mainly dependent on β-arrestin. ACKR3 has also been shown to continuously cycle between the plasma membrane and the endosomal compartments, suggesting a possible role as a scavenging receptor. So far, the molecular basis accounting for these atypical binding and signalling properties remains elusive. Noteworthy, ACKR3 extracellular domains bear three disulphide bridges. Two of them lie on top of the two main binding subpockets and are conserved among chemokine receptors, and one, specific to ACKR3, forms an intra-N terminus four-residue-loop of so far unknown function. Here, by mutational and functional studies, we examined the impact of the different disulphide bridges for ACKR3 folding, ligand binding and activation. We showed that, in contrast to most classical chemokine receptors, none of the extracellular disulphide bridges was essential for ACKR3 function. However, the disruption of the unique ACKR3 N-terminal loop drastically reduced the binding of CC chemokines whereas it only had a mild impact on CXC chemokine binding. Mutagenesis also uncovered that chemokine and endogenous non-chemokine ligands interact and activate ACKR3 according to distinct binding modes characterized by different transmembrane domain subpocket occupancy and N-terminal loop contribution, with BAM22 mimicking the binding mode of CC chemokine N terminus [less ▲]

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See detailDifferent contribution of chemokine N-terminal features attest a different ligand binding mode and a bias towards activation of the atypical chemokine receptor ACKR3/CXCR7 compared to CXCR4 and CXCR3
szpakowska, Martyna; Nevins, Amanda M; Meyrath, Max et al

in British Journal of Pharmacology (2018), 175(9), 1419-1438

Background and purpose Chemokines and their receptors form an intricate interaction and signaling network that plays critical roles in various physiological and pathological cellular processes. The high ... [more ▼]

Background and purpose Chemokines and their receptors form an intricate interaction and signaling network that plays critical roles in various physiological and pathological cellular processes. The high promiscuity and apparent redundancy of this network makes probing individual chemokine/receptor interactions and functional effects, as well as targeting individual receptor axes for therapeutic applications, challenging. Despite poor sequence identity, the N-terminal regions of chemokines, which play a key role in their activity and selectivity, harbor several conserved features. Thus far, little is known regarding the molecular basis of their interactions with conventional vs. atypical chemokine receptors or the conservation of their contributions across chemokine-receptor pairs. Experimental Approach In this study, using a broad panel of chemokine variants and modified peptides derived from the N-terminal region of chemokines CXCL12, CXCL11, and vCCL2, we compare the role of various features in binding and activation of their shared receptors, the two canonical G protein-signaling receptors, CXCR4 and CXCR3, as well as the atypical scavenger receptor CXCR7/ACKR3, which shows exclusively arrestin-dependent activity. Key Results We provide exhaustive molecular insights into the plasticity of the ligand-binding pockets of these receptors, their chemokine binding modes, and their activation mechanisms. We show that, although the chemokine N-terminal region is a critical determinant, neither the most proximal residues nor the N-loop are essential for ACKR3 binding and activation, as opposed to CXCR4 and CXCR3. Conclusion and Implications These results suggest a different interaction mechanism between this atypical receptor and its ligands and illustrates its strong propensity to activation. [less ▲]

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See detailLa souris, le patient, et le faux expert. Décryptage d'une mystification.
Bakker, Julie ULiege; Balthazart, Jacques ULiege; Baron, Frédéric ULiege et al

Article for general public (2018)

La recherche sur animaux est actuellement encadrée de façon stricte en Wallonie comme dans toute l'Union Européenne (voir l'article de Marc Vandenheede publié dans le Vif). Cette législation et les ... [more ▼]

La recherche sur animaux est actuellement encadrée de façon stricte en Wallonie comme dans toute l'Union Européenne (voir l'article de Marc Vandenheede publié dans le Vif). Cette législation et les contrôles qui y sont associés induisent de nombreuses contraintes pratiques, des charges administratives et des coûts financiers importants que les chercheurs seraient certainement heureux d'éviter s'il existait une alternative à l'expérimentation animale. [less ▲]

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See detailL'expérimentation animale ne se fait pas en dehors de tout contrôle (OPINION)
Muraille, Eric; de Kerchove d'Exaerde, Alban; Blanpain, Cedric et al

Article for general public (2018)

Proposer de réduire l'expérimentation animale pour raisons morales est louable. Mais ce choix de société ne doit pas être vendu au citoyen en lui laissant croire que la recherche conserverait la même ... [more ▼]

Proposer de réduire l'expérimentation animale pour raisons morales est louable. Mais ce choix de société ne doit pas être vendu au citoyen en lui laissant croire que la recherche conserverait la même qualité ou en serait améliorée. [less ▲]

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See detailCapillary electrophoretic mobility shift displacement assay for the assessment of weak drug-protein interactions
Farcas, Elena ULiege; Hanson, Julien ULiege; Pochet, Lionel et al

in Analytica Chimica Acta (2018)

Only few reports describe the use of capillary electrophoresis in the context of Fragment Based Drug Discovery (FBDD). In this paper, we will present a generic, fully automated, microscale electrophoretic ... [more ▼]

Only few reports describe the use of capillary electrophoresis in the context of Fragment Based Drug Discovery (FBDD). In this paper, we will present a generic, fully automated, microscale electrophoretic mobility shift competition assay that can be used in FBDD for primary screening of weak biomolecular interactions between fragments and target protein. The accuracy and reliability of the present method was demonstrated by measuring the interaction between two known fragments inhibiting thrombin, namely benzamidine and p-aminobenzamidine and a relatively weak inhibitor, nafamostat. The measured IC50 were found to be in good accordance with the previously reported ones. Furthermore, we built a small chemical library to evaluate the performance and the advantage of our newly developed screening-bioassay compared to the direct affinity capillary electrophoresis-binding assay. The results demonstrate the high discriminatory power of the method and above all its ability to screen neutral, negatively or positively charged molecules, as well as molecules that have no or low UV-VIS absorbance, greatly expanding the scope of the assay. Finally, we proved that this approach is able to discriminate between competitive binders and irreversible binders. Altogether, this work demonstrates that capillary electrophoresis could constitute an important added value in the arsenal used to screen fragments in drug discovery. [less ▲]

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See detailMutational analysis of the extracellular disulphide bridges of the atypical chemokine receptor ACKR3/CXCR7 uncovers multiple binding and activation modes for its chemokine and endogenous non-chemokine agonists
Szpakowska, Martyna; Meyrath, Max Marc Roger ULiege; Reynders, Nathan et al

in Biochemical Pharmacology (2018), 153

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike ... [more ▼]

The atypical chemokine receptor ACKR3/CXCR7 plays crucial roles in numerous physiological processes but also in viral infection and cancer. ACKR3 shows strong propensity for activation and, unlike classical chemokine receptors, can respond to chemokines from both the CXC and CC families as well as to the endogenous peptides BAM22 and adrenomedullin. Moreover, despite belonging to the G protein coupled receptor family, its function appears to be mainly dependent on β-arrestin. ACKR3 has also been shown to continuously cycle between the plasma membrane and the endosomal compartments, suggesting a possible role as a scavenging receptor. So far, the molecular basis accounting for these atypical binding and signalling properties remains elusive. Noteworthy, ACKR3 extracellular domains bear three disulphide bridges. Two of them lie on top of the two main binding subpockets and are conserved among chemokine receptors, and one, specific to ACKR3, forms an intra-N terminus four-residue-loop of so far unknown function. Here, by mutational and functional studies, we examined the impact of the different disulphide bridges for ACKR3 folding, ligand binding and activation. We showed that, in contrast to most classical chemokine receptors, none of the extracellular disulphide bridges was essential for ACKR3 function. However, the disruption of the unique ACKR3 N-terminal loop drastically reduced the binding of CC chemokines whereas it only had a mild impact on CXC chemokine binding. Mutagenesis also uncovered that chemokine and endogenous non-chemokine ligands interact and activate ACKR3 according to distinct binding modes characterized by different transmembrane domain subpocket occupancy and N-terminal loop contribution, with BAM22 mimicking the binding mode of CC chemokine N terminus. [less ▲]

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See detailEnhancing Action of Positive Allosteric Modulators through the Design of Dimeric Compounds
Drapier, Thomas ULiege; Geubelle, Pierre ULiege; Bouckaert, Charlotte et al

in Journal of Medicinal Chemistry (2018)

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See detail7‐Phenoxy-Substituted 3,4-Dihydro‐2H‐1,2,4-benzothiadiazine 1,1- Dioxides as Positive Allosteric Modulators of α‐Amino-3-hydroxy-5- methyl-4-isoxazolepropionic Acid (AMPA) Receptors with Nanomolar Potency
Goffin, Eric ULiege; Drapier, Thomas ULiege; Probst Larsen, Anja et al

in Journal of Medicinal Chemistry (2018), 61

We report here the synthesis of 7-phenoxy- substituted 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides and their evaluation as AMPA receptor positive allosteric modulators (AMPApams). The impact of ... [more ▼]

We report here the synthesis of 7-phenoxy- substituted 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides and their evaluation as AMPA receptor positive allosteric modulators (AMPApams). The impact of substitution on the phenoxy ring and on the nitrogen atom at the 4-position was examined. At GluA2(Q) expressed in HEK293 cells (calcium flux experiment), the most potent compound was 11m (4- cyclopropyl-7-(3-methoxyphenoxy)-3,4-dihydro-2H-1,2,4-ben- zothiadiazine 1,1-dioxide, EC50 = 2.0 nM). The Hill coefficient in the screening and the shape of the dimerization curve in small-angle X-ray scattering (SAXS) experiments using isolated GluA2 ligand-binding domain (GluA2-LBD) are consistent with binding of one molecule of 11m per dimer interface, contrary to most benzothiadiazine dioxides developed to date. This observation was confirmed by the X-ray structure of 11m bound to GluA2-LBD and by NMR. This is the first benzothiadiazine dioxide AMPApam to reach the nanomolar range. [less ▲]

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See detailL’expérimentation animale reste indispensable (OPINION)
Amorim, Christiani; Andris, Fabienne; Arckens, Lut et al

Article for general public (2017)

Trop fréquemment, l’expérimentation animale est présentée comme une pratique archaïque. Elle a bien changé. Et 100 % des patients traités le sont grâce aux concepts et techniques développés grâce à elle.

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See detailTargeted mutagenesis of orphan GPCRs of the SREB family
Laschet, Céline ULiege; Dupuis, Nadine ULiege; Geubelle, Pierre ULiege et al

Poster (2017, September)

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See detailPharmacology of GPR101
Abboud, Dayana ULiege; Daly, Adrian ULiege; Laschet, Céline ULiege et al

Conference (2017, July 07)

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See detailActivation of the orphan G protein-coupled receptor GPR27 by surrogate ligands promotes β-arrestin 2 recruitment
Dupuis, Nadine ULiege; Laschet, Céline ULiege; Franssen, Delphine ULiege et al

in Molecular Pharmacology (2017), 91(6), 595-608

G protein-coupled receptors are the most important drug targets for human diseases. An important number of them remain devoid of confirmed ligands. GPR27 is one of these orphan receptors, characterized by ... [more ▼]

G protein-coupled receptors are the most important drug targets for human diseases. An important number of them remain devoid of confirmed ligands. GPR27 is one of these orphan receptors, characterized by a high level of conservation among vertebrates and a predominant expression in the central nervous system. In addition, it has recently been linked to insulin secretion. However, the absence of endogenous or surrogate ligands for GPR27 complicates the examination of its biological function. Our aim was to validate GPR27 signaling pathways and therefore we sought to screen a diversity oriented synthesis library to identify GPR27-specific surrogate agonists. In order to select an optimal screening assay, we investigated GPR27 ligand-independent activity. Both in G protein-mediated pathways and in β-arrestin 2 recruitment, no ligand-independent activity could be measured. However, we observed a recruitment of β-arrestin 2 to a GPR27V2 chimera in the presence of membrane-anchored β-adrenergic receptor kinase 1 (GRK2). Therefore, we optimized a firefly luciferase complementation assay to screen against this chimeric receptor. We identified two compounds (N-[4-(anilinocarbonyl)phenyl]-2,4-dichlorobenzamide (ChemBridge ID5128535) and 2,4-dichloro-N-{4-[(1,3-thiazol-2-ylamino)sulfonyl]phenyl}benzamide (ChemBridge ID5217941)) sharing a N-phenyl-2,4-dichlorobenzamide scaffold, which were selective for GPR27 over its closely related family members GPR85 and GPR173. The specificity of the activity was confirmed with a NanoBiT® β-arrestin 2 assay, imaging of GFP-tagged β-arrestin 2 and PathHunter® β-arrestin 2 Assay. Interestingly, no G protein activation was detected upon activation of GPR27 by these compounds. Our study provides the first selective surrogate agonists for the orphan GPR27. [less ▲]

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See detailDiscovery and pharmacological characterization of succinate receptor (SUCNR1/GPR91) agonists
Geubelle, Pierre ULiege; Gilissen, Julie; Dilly, Sebastien et al

in British Journal of Pharmacology (2017), 174(9), 796-808

Background and Purpose The succinate receptor (SUCNR1 or GPR91) has been described as a metabolic sensor that may be involved in homeostasis. Notwithstanding its implication in important (patho ... [more ▼]

Background and Purpose The succinate receptor (SUCNR1 or GPR91) has been described as a metabolic sensor that may be involved in homeostasis. Notwithstanding its implication in important (patho)physiological processes, the function of SUCNR1 has remained elusive because no pharmacological tools were available. We report on the discovery of the first family of synthetic potent agonists. Experimental Approach We screened a library of succinate analogues and analysed their activity on SUCNR1. In addition, we modelled a pharmacophore and a binding site for the receptor. New agonists were identified based on the information provided by these two approaches. Their activity was studied in various bioassays, including measurement of cAMP levels, [Ca2+]i mobilisation, TGF-α shedding and recruitment of arrestin 3. The in vivo impact of SUCNR1 activation by these new agonists was evaluated on rat blood pressure. Key Results We identified cis-epoxysuccinic acid and cis-1,2-cyclopropanedicarboxylic acid as agonists with an efficacy similar to the one of succinic acid. Interestingly, cis-epoxysuccinic acid was characterized by a 10 to 20 fold higher potency than succinate on the receptor. For example, cis-epoxysuccinic acid reduced cAMP levels with a pEC50 = 5.57 ± 0.02 (EC50 = 2.7 μM) as compared to succinate pEC50 = 4.54 ± 0.08 (EC50 = 29 μM). The rank order of potency of the three agonists was the same in all bioassays tested. In vivo, cis-epoxysuccinic and cis-1,2-cyclopropanedicarboxylic acid increased rat blood pressure to the same extent as succinate did. Conclusions and Implications We provide new agonist tools for SUCNR1 that should facilitate further research on this understudied receptor. [less ▲]

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