1
|
Liu A, Liu Y, Zhang W, Ye RD. Structural insights into ligand recognition and activation of the succinate receptor SUCNR1. Cell Rep 2024; 43:114381. [PMID: 38923454 DOI: 10.1016/j.celrep.2024.114381] [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: 04/18/2024] [Revised: 05/24/2024] [Accepted: 06/03/2024] [Indexed: 06/28/2024] Open
Abstract
Succinate, a citric acid cycle intermediate, serves important functions in energy homeostasis and metabolic regulation. Extracellular succinate acts as a stress signal through succinate receptor (SUCNR1), a class A G protein-coupled receptor. Research on succinate signaling is hampered by the lack of high-resolution structures of the agonist-bound receptor. We present cryoelectron microscopy (cryo-EM) structures of SUCNR1-Gi complexes bound to succinate and its non-metabolite derivative cis-epoxysuccinate. Key determinants for the recognition of succinate in cis conformation include R2817.39 and Y832.64, while Y301.39 and R993.29 participate in the binding of both succinate and cis-epoxysuccinate. Extracellular loop 2, through F175ECL2 in its β-hairpin, forms a hydrogen bond with succinate and caps the binding pocket. At the receptor-Gi interface, agonist binding induces the rearrangement of a hydrophobic network on transmembrane (TM)5 and TM6, leading to TM signaling through TM3 and TM7. These findings extend our understanding of succinate recognition by SUCNR1, aiding the development of therapeutics for the succinate receptor.
Collapse
Affiliation(s)
- Aijun Liu
- Dongguan Songshan Lake Central Hospital, Dongguan Third People's Hospital, The Affiliated Dongguan Songshan Lake Central Hospital, Guangdong Medical University, Dongguan, Guangdong 523326, China; Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China; The Chinese University of Hong Kong, Shenzhen Futian Biomedical Innovation R&D Center, Shenzhen, Guangdong 518000, China.
| | - Yezhou Liu
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China; The Chinese University of Hong Kong, Shenzhen Futian Biomedical Innovation R&D Center, Shenzhen, Guangdong 518000, China
| | - Weijia Zhang
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
| | - Richard D Ye
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China; The Chinese University of Hong Kong, Shenzhen Futian Biomedical Innovation R&D Center, Shenzhen, Guangdong 518000, China.
| |
Collapse
|
2
|
Shenol A, Lückmann M, Trauelsen M, Lambrughi M, Tiberti M, Papaleo E, Frimurer TM, Schwartz TW. Molecular dynamics-based identification of binding pathways and two distinct high-affinity sites for succinate in succinate receptor 1/GPR91. Mol Cell 2024; 84:955-966.e4. [PMID: 38325379 DOI: 10.1016/j.molcel.2024.01.011] [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: 04/06/2023] [Revised: 11/30/2023] [Accepted: 01/16/2024] [Indexed: 02/09/2024]
Abstract
SUCNR1 is an auto- and paracrine sensor of the metabolic stress signal succinate. Using unsupervised molecular dynamics (MD) simulations (170.400 ns) and mutagenesis across human, mouse, and rat SUCNR1, we characterize how a five-arginine motif around the extracellular pole of TM-VI determines the initial capture of succinate in the extracellular vestibule (ECV) to either stay or move down to the orthosteric site. Metadynamics demonstrate low-energy succinate binding in both sites, with an energy barrier corresponding to an intermediate stage during which succinate, with an associated water cluster, unlocks the hydrogen-bond-stabilized conformationally constrained extracellular loop (ECL)-2b. Importantly, simultaneous binding of two succinate molecules through either a "sequential" or "bypassing" mode is a frequent endpoint. The mono-carboxylate NF-56-EJ40 antagonist enters SUCNR1 between TM-I and -II and does not unlock ECL-2b. It is proposed that occupancy of both high-affinity sites is required for selective activation of SUCNR1 by high local succinate concentrations.
Collapse
Affiliation(s)
- Aslihan Shenol
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael Lückmann
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mette Trauelsen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matteo Lambrughi
- Cancer Structural Biology, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Matteo Tiberti
- Cancer Structural Biology, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Elena Papaleo
- Cancer Structural Biology, Danish Cancer Society Research Center, Copenhagen, Denmark; Cancer Systems Biology, Section for Bioinformatics, Department of Health and Technology, Technical University of Denmark, Lyngby, Denmark
| | - Thomas M Frimurer
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thue W Schwartz
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
3
|
Tian Q, Ruan J, Wang Y, Xiao Y, Cheng Q, Chen Y, Li M, Chang K, Yi X. Extracellular succinate derived from ectopic milieu drives adhesion and implantation growth of ectopic endometrial stromal cells via the SUCNR1 signal in endometriosis. Cell Commun Signal 2024; 22:82. [PMID: 38291428 PMCID: PMC10826047 DOI: 10.1186/s12964-023-01415-7] [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: 08/28/2023] [Accepted: 12/02/2023] [Indexed: 02/01/2024] Open
Abstract
BACKGROUND As a dual-function metabolite, succinate has emerged in cell function and plays a key signaling role in linking mitochondrial function to other cellular functions. Succinate accumulation in the cytoplasm is commonly associated with hypoxia in the microenvironment and immune cell activation. Extracellular succinate released into the microenvironment is considered an inflammatory alarm that can be sensed by its membrane receptor SUCNR1, which boosts proinflammatory responses and acts akin to classical hormones and cytokines. Succinate plays an important role in the development of inflammatory diseases. Whether succinate facilitates the progression of endometriosis (EMs), characterized by chronic inflammation and peritoneal adhesion, is worth exploring. OBJECTIVE We mimicked the ectopic milieu in vitro and in vivo to evaluate the main source and potential role of succinate in endometriosis. We assessed the molecular and functional effects of succinate on macrophages and peritoneal mesothelial cells in peritoneal cavity. The effect of succinate/SUCNR1 signaling on ectopic endometrial stromal cells (ESCs) was further explored in this study. METHODS In this study, we used targeted organic acid metabolomics analysis and in vitro assays to assess the potential accumulation of succinate in the peritoneal fluid of EMs patients. We examined its correlation with disease severity, Visual Analogue Scale, and the Endometriosis Fertility Index. Flow cytometry, enzyme linked immunosorbent assay, western blot assay, quantitative real-time PCR, and other molecular biology techniques were used to explore the potential mechanisms. RESULTS By mimicking the ectopic milieu, we constructed an in vitro co-culture system and found that M1 polarized macrophages and that the peritoneal mesothelial cell line (HMrSV5) mainly released succinate into their microenvironment and activated the succinate receptor (SUCNR1) signal, which further polarized the macrophages and significantly enhanced the invasive survival of ESCs, and the adhesion to the peritoneum. We further investigated the pathological effects of extracellular succinate in vivo using a xenograft mouse models of endometriosis. CONCLUSIONS Succinate-SUCNR1 signaling facilitates the creation of inflammatory cells and plays a vital role in EMs progression and peritoneal adhesion. Our work on the molecular mechanisms underlying succinate accumulation and function will help elucidate the phenotypic mysteries of pain and infertility in EMs. Video Abstract.
Collapse
Affiliation(s)
- Qi Tian
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China
| | - Jingyao Ruan
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China
| | - Yuning Wang
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China
| | - Yinping Xiao
- Department of Pathology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China
| | - Qi Cheng
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China
| | - Yun Chen
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China
| | - Mingqing Li
- Laboratory for Reproductive Immunology, Hospital of Obstetrics and Gynecology, Fudan University, Shanghai, 200011, People's Republic of China
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China
| | - Kaikai Chang
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China.
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China.
| | - Xiaofang Yi
- Department of Gynecology, Hospital of Obstetrics and Gynecology, Fudan University, 419# Fangxie Road, Shanghai, 200011, China.
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China.
| |
Collapse
|
4
|
Griepke S, Trauelsen M, Nilsson MD, Hansen J, Steffensen LB, Schwartz TW, Ketelhuth DFJ. G-Protein-Coupled Receptor 91-Dependent Signalling Does Not Influence Vascular Inflammation and Atherosclerosis in Hyperlipidaemic Mice. Cells 2023; 12:2580. [PMID: 37947659 PMCID: PMC10647868 DOI: 10.3390/cells12212580] [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: 09/28/2023] [Revised: 10/31/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023] Open
Abstract
The TCA cycle intermediate metabolite 'succinate' has been proposed as an inflammatory mediator, influencing autoimmunity and allergic reactions, through ligation to its sensing receptor SUCNR1/GPR91. Whether GPR91-mediated signalling influences the chronic inflammatory process of atherosclerosis has never been investigated. The examination of publicly available datasets revealed that the SUCNR1 gene is expressed in human atherosclerotic plaques, especially in vascular smooth muscle cells. Using GPR91 knockout (Gpr91-/-) and wildtype (WT) littermates, made hyperlipidaemic with the overexpression of the gain-of-function mutated Pcsk9 and Western diet feeding, we showed that the full ablation of GPR91 did not accelerate atherosclerosis-lesions in the aortic arch 2.18 ± 0.48% vs. 1.64 ± 0.31%, and in the aortic roots 10.06 ± 0.91% vs. 10.67 ± 1.53% for Gpr91-/- and WT mice, respectively. In line with this, no differences between groups were observed for macrophage and T-cell infiltration in the plaque, as well as the polarization towards M1- or M2-like macrophages in the aorta, spleen and liver of Gpr91-/- and WT control mice. In conclusion, our study indicates that the global ablation of GPR91 signalling does not influence vascular inflammation or atherogenesis.
Collapse
Affiliation(s)
- Silke Griepke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark; (S.G.); (M.D.N.); (J.H.); (L.B.S.)
| | - Mette Trauelsen
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen, Denmark; (M.T.); (T.W.S.)
| | - Michelle D. Nilsson
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark; (S.G.); (M.D.N.); (J.H.); (L.B.S.)
| | - Jakob Hansen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark; (S.G.); (M.D.N.); (J.H.); (L.B.S.)
| | - Lasse B. Steffensen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark; (S.G.); (M.D.N.); (J.H.); (L.B.S.)
| | - Thue W. Schwartz
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, 2200 Copenhagen, Denmark; (M.T.); (T.W.S.)
| | - Daniel F. J. Ketelhuth
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, 5000 Odense, Denmark; (S.G.); (M.D.N.); (J.H.); (L.B.S.)
- Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Bioclinicum, Solna, 171 64 Stockholm, Sweden
| |
Collapse
|
5
|
Abstract
Lactate released from skeletal muscle during high-intensity exercise gives rise to a surge in circulating lactate-derived pseudo-dipeptide metabolites including N-lactoyl-phenylalanine (Lac-Phe). In a recent Nature paper, Li et al. use genetic and pharmacological evidence to now propose Lac-Phe to be an "exercise hormone" that suppresses appetite and obesity.
Collapse
Affiliation(s)
- Jens Lund
- Novo Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christoffer Clemmensen
- Novo Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Thue W Schwartz
- Novo Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
6
|
Why succinate? Physiological regulation by a mitochondrial coenzyme Q sentinel. Nat Chem Biol 2022; 18:461-469. [PMID: 35484255 PMCID: PMC9150600 DOI: 10.1038/s41589-022-01004-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 02/25/2022] [Indexed: 12/15/2022]
Abstract
Metabolites once considered solely in catabolism or anabolism turn out to have key regulatory functions. Among these, the citric acid cycle intermediate succinate stands out owing to its multiple roles in disparate pathways, its dramatic concentration changes and its selective cell release. Here we propose that succinate has evolved as a signaling modality because its concentration reflects the coenzyme Q (CoQ) pool redox state, a central redox couple confined to the mitochondrial inner membrane. This connection is of general importance because CoQ redox state integrates three bioenergetic parameters: mitochondrial electron supply, oxygen tension and ATP demand. Succinate, by equilibrating with the CoQ pool, enables the status of this central bioenergetic parameter to be communicated from mitochondria to the rest of the cell, into the circulation and to other cells. The logic of this form of regulation explains many emerging roles of succinate in biology, and suggests future research questions.
Collapse
|
7
|
Strassheim D, Sullivan T, Irwin DC, Gerasimovskaya E, Lahm T, Klemm DJ, Dempsey EC, Stenmark KR, Karoor V. Metabolite G-Protein Coupled Receptors in Cardio-Metabolic Diseases. Cells 2021; 10:3347. [PMID: 34943862 PMCID: PMC8699532 DOI: 10.3390/cells10123347] [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] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/10/2021] [Accepted: 11/18/2021] [Indexed: 12/15/2022] Open
Abstract
G protein-coupled receptors (GPCRs) have originally been described as a family of receptors activated by hormones, neurotransmitters, and other mediators. However, in recent years GPCRs have shown to bind endogenous metabolites, which serve functions other than as signaling mediators. These receptors respond to fatty acids, mono- and disaccharides, amino acids, or various intermediates and products of metabolism, including ketone bodies, lactate, succinate, or bile acids. Given that many of these metabolic processes are dysregulated under pathological conditions, including diabetes, dyslipidemia, and obesity, receptors of endogenous metabolites have also been recognized as potential drug targets to prevent and/or treat metabolic and cardiovascular diseases. This review describes G protein-coupled receptors activated by endogenous metabolites and summarizes their physiological, pathophysiological, and potential pharmacological roles.
Collapse
Affiliation(s)
- Derek Strassheim
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Timothy Sullivan
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - David C. Irwin
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Evgenia Gerasimovskaya
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Tim Lahm
- Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health Denver, Denver, CO 80206, USA;
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
| | - Dwight J. Klemm
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
- Division of Pulmonary Sciences and Critical Care Medicine, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Edward C. Dempsey
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA
- Division of Pulmonary Sciences and Critical Care Medicine, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kurt R. Stenmark
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
| | - Vijaya Karoor
- Department of Medicine Cardiovascular and Pulmonary Research Laboratory, University of Colorado Denver, Denver, CO 80204, USA; (D.S.); (T.S.); (D.C.I.); (E.G.); (D.J.K.); (E.C.D.); (K.R.S.)
- Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health Denver, Denver, CO 80206, USA;
- Division of Pulmonary Sciences and Critical Care Medicine, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| |
Collapse
|