1
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Srinivasan S, Álvarez D, John Peter AT, Vanni S. Unbiased MD simulations identify lipid binding sites in lipid transfer proteins. J Cell Biol 2024; 223:e202312055. [PMID: 39105757 DOI: 10.1083/jcb.202312055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 05/29/2024] [Accepted: 07/16/2024] [Indexed: 08/07/2024] Open
Abstract
The characterization of lipid binding to lipid transfer proteins (LTPs) is fundamental to understand their molecular mechanism. However, several structures of LTPs, and notably those proposed to act as bridges between membranes, do not provide the precise location of their endogenous lipid ligands. To address this limitation, computational approaches are a powerful alternative methodology, but they are often limited by the high flexibility of lipid substrates. Here, we develop a protocol based on unbiased coarse-grain molecular dynamics simulations in which lipids placed away from the protein can spontaneously bind to LTPs. This approach accurately determines binding pockets in LTPs and provides a working hypothesis for the lipid entry pathway. We apply this approach to characterize lipid binding to bridge LTPs of the Vps13-Atg2 family, for which the lipid localization inside the protein is currently unknown. Overall, our work paves the way to determine binding pockets and entry pathways for several LTPs in an inexpensive, fast, and accurate manner.
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Affiliation(s)
| | - Daniel Álvarez
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- Departamento de Química Física y Analítica, Universidad de Oviedo, Oviedo, España
| | - Arun T John Peter
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- Swiss National Center for Competence in Research Bio-inspired Materials, University of Fribourg , Fribourg, Switzerland
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2
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Lin YC, Swendeman S, Moreira IS, Ghosh A, Kuo A, Rosário-Ferreira N, Guo S, Culbertson A, Levesque MV, Cartier A, Seno T, Schmaier A, Galvani S, Inoue A, Parikh SM, FitzGerald GA, Zurakowski D, Liao M, Flaumenhaft R, Gümüş ZH, Hla T. Designer high-density lipoprotein particles enhance endothelial barrier function and suppress inflammation. Sci Signal 2024; 17:eadg9256. [PMID: 38377179 PMCID: PMC10954247 DOI: 10.1126/scisignal.adg9256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 01/31/2024] [Indexed: 02/22/2024]
Abstract
High-density lipoprotein (HDL) nanoparticles promote endothelial cell (EC) function and suppress inflammation, but their utility in treating EC dysfunction has not been fully explored. Here, we describe a fusion protein named ApoA1-ApoM (A1M) consisting of apolipoprotein A1 (ApoA1), the principal structural protein of HDL that forms lipid nanoparticles, and ApoM, a chaperone for the bioactive lipid sphingosine 1-phosphate (S1P). A1M forms HDL-like particles, binds to S1P, and is signaling competent. Molecular dynamics simulations showed that the S1P-bound ApoM moiety in A1M efficiently activated EC surface receptors. Treatment of human umbilical vein ECs with A1M-S1P stimulated barrier function either alone or cooperatively with other barrier-enhancing molecules, including the stable prostacyclin analog iloprost, and suppressed cytokine-induced inflammation. A1M-S1P injection into mice during sterile inflammation suppressed neutrophil influx and inflammatory mediator secretion. Moreover, systemic A1M administration led to a sustained increase in circulating HDL-bound S1P and suppressed inflammation in a murine model of LPS-induced endotoxemia. We propose that A1M administration may enhance vascular endothelial barrier function, suppress cytokine storm, and promote resilience of the vascular endothelium.
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Affiliation(s)
- Yueh-Chien Lin
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Steven Swendeman
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Irina S. Moreira
- Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
- CNC - Center for Neuroscience and Cell Biology, Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3000-456, Coimbra, Portugal
| | - Avishek Ghosh
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Andrew Kuo
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Nícia Rosário-Ferreira
- CNC - Center for Neuroscience and Cell Biology, Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3000-456, Coimbra, Portugal
| | | | - Alan Culbertson
- Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA
| | - Michel V. Levesque
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Andreane Cartier
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Takahiro Seno
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Alec Schmaier
- Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, 02115, USA
| | - Sylvain Galvani
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Samir M. Parikh
- Division of Nephrology and Department of Medicine, Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, 75235, USA
| | - Garret A. FitzGerald
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, PA, 19104, USA
| | - David Zurakowski
- Department of Anesthesia and Surgery, Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Maofu Liao
- Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA
- Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
- Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China
| | | | - Zeynep H. Gümüş
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA and Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Timothy Hla
- Vascular Biology Program, Boston Children’s Hospital and Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
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3
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Structural basis of sphingosine-1-phosphate receptor 1 activation and biased agonism. Nat Chem Biol 2021; 18:281-288. [PMID: 34937912 DOI: 10.1038/s41589-021-00930-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 10/21/2021] [Indexed: 12/20/2022]
Abstract
Sphingosine-1-phosphate receptor 1 (S1PR1) is a master regulator of lymphocyte egress from the lymph node and an established drug target for multiple sclerosis (MS). Mechanistically, therapeutic S1PR1 modulators activate the receptor yet induce sustained internalization through a potent association with β-arrestin. However, a structural basis of biased agonism remains elusive. Here, we report the cryo-electron microscopy (cryo-EM) structures of Gi-bound S1PR1 in complex with S1P, fingolimod-phosphate (FTY720-P) and siponimod (BAF312). In combination with functional assays and molecular dynamics (MD) studies, we reveal that the β-arrestin-biased ligands direct a distinct activation path in S1PR1 through the extensive interplay between the PIF and the NPxxY motifs. Specifically, the intermediate flipping of W2696.48 and the retained interaction between F2656.44 and N3077.49 are the key features of the β-arrestin bias. We further identify ligand-receptor interactions accounting for the S1PR subtype specificity of BAF312. These structural insights provide a rational basis for designing novel signaling-biased S1PR modulators.
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4
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Kobayashi T, Kurano M, Nanya M, Shimizu T, Ohkawa R, Tozuka M, Yatomi Y. Glycation of HDL Polymerizes Apolipoprotein M and Attenuates Its Capacity to Bind to Sphingosine 1-Phosphate. J Atheroscler Thromb 2021; 28:730-741. [PMID: 32999208 PMCID: PMC8265924 DOI: 10.5551/jat.55699] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aim:
Recently, it has been established that most of the pleiotropic effects of high-density lipoprotein (HDL) are attributed to sphingosine 1-phosphate (S1P), which rides on HDL via apolipoprotein M (ApoM). In subjects with diabetes mellitus, both the pleiotropic effects of HDL and its role in reverse cholesterol transport are reported to be impaired. To elucidate the mechanisms underlying the impaired pleiotropic effects of HDL in subjects with diabetes, from the aspects of S1P and ApoM.
Methods:
The incubation of HDL in a high-glucose condition resulted in the dimerization of ApoM. Moreover, the treatment of HDL with methylglyoxal resulted in the modulation of the ApoM structure, as suggested by the results of western blot analysis, isoelectric focusing electrophoresis, and two-dimensional gel electrophoresis, which was reversed by treatment with anti-glycation reagents.
Results:
The glycation of HDL resulted in impaired binding of the glycated HDL to S1P, and the S1P on glycated HDL degraded faster. In the case of human subjects, on the other hand, although both the serum ApoM levels and the ApoM content in HDL were lower in subjects with diabetes, we did not observe the polymerization of ApoM.
Conclusions:
Modulation of the quantity and quality of ApoM might explain, at least in part, the impaired functions of HDL in subjects with diabetes mellitus. ApoM might be a useful target for laboratory testing and/or the treatment of diabetes mellitus.
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Affiliation(s)
- Tamaki Kobayashi
- Department of Clinical Laboratory Medicine, The University of Tokyo.,Analytical Laboratory Chemistry, Graduate School of Health Care Sciences, Tokyo Medical and Dental University
| | - Makoto Kurano
- Department of Clinical Laboratory Medicine, The University of Tokyo
| | - Mai Nanya
- Department of Clinical Laboratory Medicine, The University of Tokyo
| | - Tomo Shimizu
- Research and Development Division, Tsukuba Research Institute, Sekisui Medical Co., Ltd
| | - Ryunosuke Ohkawa
- Analytical Laboratory Chemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Minoru Tozuka
- Life Science Research Center, Nagano Children's Hospital
| | - Yutaka Yatomi
- Department of Clinical Laboratory Medicine, The University of Tokyo
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5
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Mücke VT, Maria Schwarzkopf K, Thomas D, Mücke MM, Rüschenbaum S, Trebicka J, Pfeilschifter J, Zeuzem S, Lange CM, Grammatikos G. Serum Sphingosine-1-Phosphate Is Decreased in Patients With Acute-on-Chronic Liver Failure and Predicts Early Mortality. Hepatol Commun 2020; 4:1477-1486. [PMID: 33024917 PMCID: PMC7527696 DOI: 10.1002/hep4.1561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/17/2020] [Accepted: 06/10/2020] [Indexed: 12/30/2022] Open
Abstract
Sphingosine‐1‐phosphate (S1P) regulates pathophysiological processes, including liver regeneration, vascular tone control, and immune response. In patients with liver cirrhosis, acute deterioration of liver function is associated with high mortality rates. The present study investigated whether serum S1P concentrations are associated with disease severity in patients with chronic liver disease from compensated cirrhosis (CC), acute decompensation (AD), or acute‐on‐chronic liver failure (ACLF). From August 2013 to October 2017, patients who were admitted to the University Hospital Frankfurt with CC, AD, or ACLF were enrolled in our cirrhosis cohort study. Tandem mass spectrometry was performed on serum samples of 127 patients to assess S1P concentration. Our study comprised 19 patients with CC, 55 with AD, and 51 with ACLF, aged 29 to 76 years. We observed a significant decrease of S1P according to advanced liver injury from CC and AD up to ACLF (P < 0.001). S1P levels further decreased with progression to ACLF grade 3 (P < 0.05), and S1P highly inversely correlated with the Model for End‐Stage Liver Disease score (r = −0.508; P < 0.001). In multivariate analysis, S1P remained an independent predictor of 7‐day mortality with high diagnostic accuracy (area under the curve, 0.874; P < 0.001). Conclusion: In patients with chronic liver disease, serum S1P levels dramatically decreased with advanced stages of liver disease and were predictive of early mortality. Because S1P is a potent regulator of endothelial integrity and immune response, low S1P levels may significantly influence progressive multiorgan failure. Our data justify further elucidation of the diagnostic and therapeutic role of S1P in ACLF.
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Affiliation(s)
- Victoria T Mücke
- Departement of Internal Medicine 1 University Hospital Frankfurt Goethe University Frankfurt am Main Germany
| | - Katharina Maria Schwarzkopf
- Departement of Internal Medicine 1 University Hospital Frankfurt Goethe University Frankfurt am Main Germany
| | - Dominique Thomas
- Pharmazentrum Frankfurt Institute of Clinical Pharmacology Goethe University Frankfurt am Main Germany
| | - Marcus M Mücke
- Departement of Internal Medicine 1 University Hospital Frankfurt Goethe University Frankfurt am Main Germany
| | - Sabrina Rüschenbaum
- Department of Gastroenterology and Hepatology University Hospital Essen University of Duisburg-Essen Essen Germany
| | - Jonel Trebicka
- Departement of Internal Medicine 1 University Hospital Frankfurt Goethe University Frankfurt am Main Germany
| | - Josef Pfeilschifter
- Pharmazentrum Frankfurt Institute of General Pharmacology and Toxicology Goethe University Frankfurt am Main Germany
| | - Stefan Zeuzem
- Departement of Internal Medicine 1 University Hospital Frankfurt Goethe University Frankfurt am Main Germany
| | - Christian M Lange
- Department of Gastroenterology and Hepatology University Hospital Essen University of Duisburg-Essen Essen Germany
| | - Georgios Grammatikos
- Departement of Internal Medicine 1 University Hospital Frankfurt Goethe University Frankfurt am Main Germany.,St. Luke's Hospital Thessaloniki Panorama Greece
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Dhangadamajhi G, Singh S. Sphingosine 1-Phosphate in Malaria Pathogenesis and Its Implication in Therapeutic Opportunities. Front Cell Infect Microbiol 2020; 10:353. [PMID: 32923406 PMCID: PMC7456833 DOI: 10.3389/fcimb.2020.00353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 06/08/2020] [Indexed: 11/13/2022] Open
Abstract
Sphingosine 1-Phosphate (S1P) is a bioactive lipid intermediate in the sphingolipid metabolism, which exist in two pools, intracellular and extracellular, and each pool has a different function. The circulating extracellular pool, specifically the plasma S1P is shown to be important in regulating various physiological processes related to malaria pathogenesis in recent years. Although blood cells (red blood cells and platelets), vascular endothelial cells and hepatocytes are considered as the important sources of plasma S1P, their extent of contribution is still debated. The red blood cells (RBCs) and platelets serve as a major repository of intracellular S1P due to lack, or low activity of S1P degrading enzymes, however, contribution of platelets toward maintaining plasma S1P is shown negligible under normal condition. Substantial evidences suggest platelets loss during falciparum infection as a contributing factor for severe malaria. However, platelets function as a source for plasma S1P in malaria needs to be examined experimentally. RBC being the preferential site for parasite seclusion, and having the ability of trans-cellular S1P transportation to EC upon tight cell-cell contact, might play critical role in differential S1P distribution and parasite growth. In the present review, we have summarized the significance of both the S1P pools in the context of malaria, and how the RBC content of S1P can be channelized in better ways for its possible implication in therapeutic opportunities to control malaria.
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Affiliation(s)
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
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7
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A conformation-specific ON-switch for controlling CAR T cells with an orally available drug. Proc Natl Acad Sci U S A 2020; 117:14926-14935. [PMID: 32554495 PMCID: PMC7334647 DOI: 10.1073/pnas.1911154117] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Molecular ON-switches in which a chemical compound induces protein-protein interactions can allow cellular function to be controlled with small molecules. ON-switches based on clinically applicable compounds and human proteins would greatly facilitate their therapeutic use. Here, we developed an ON-switch system in which the human retinol binding protein 4 (hRBP4) of the lipocalin family interacts with engineered hRBP4 binders in a small molecule-dependent manner. Two different protein scaffolds were engineered to bind to hRBP4 when loaded with the orally available small molecule A1120. The crystal structure of an assembled ON-switch shows that the engineered binder specifically recognizes the conformational changes induced by A1120 in two loop regions of hRBP4. We demonstrate that this conformation-specific ON-switch is highly dependent on the presence of A1120, as demonstrated by an ∼500-fold increase in affinity upon addition of the small molecule drug. Furthermore, the ON-switch successfully regulated the activity of primary human CAR T cells in vitro. We anticipate that lipocalin-based ON-switches have the potential to be broadly applied for the safe pharmacological control of cellular therapeutics.
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8
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Obinata H, Hla T. Sphingosine 1-phosphate and inflammation. Int Immunol 2020; 31:617-625. [PMID: 31049553 DOI: 10.1093/intimm/dxz037] [Citation(s) in RCA: 163] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 04/10/2019] [Indexed: 11/13/2022] Open
Abstract
AbstractSphingosine 1-phosphate (S1P), a sphingolipid mediator, regulates various cellular functions via high-affinity G protein-coupled receptors, S1P1-5. The S1P-S1P receptor signaling system plays important roles in lymphocyte trafficking and maintenance of vascular integrity, thus contributing to the regulation of complex inflammatory processes. S1P is enriched in blood and lymph while maintained low in intracellular or interstitial fluids, creating a steep S1P gradient that is utilized to facilitate efficient egress of lymphocytes from lymphoid organs. Blockage of the S1P-S1P receptor signaling system results in a marked decrease in circulating lymphocytes because of a failure of lymphocyte egress from lymphoid organs. This provides a basis of immunomodulatory drugs targeting S1P1 receptor such as FTY720, an immunosuppressive drug approved in 2010 as the first oral treatment for relapsing-remitting multiple sclerosis. The S1P-S1P receptor signaling system also plays important roles in maintenance of vascular integrity since it suppresses sprouting angiogenesis and regulates vascular permeability. Dysfunction of the S1P-S1P receptor signaling system results in various vascular defects, such as exaggerated angiogenesis in developing retina and augmented inflammation due to increased permeability. Endothelial-specific deletion of S1P1 receptor in mice fed high-fat diet leads to increased formation of atherosclerotic lesions. This review highlights the importance of the S1P-S1P receptor signaling system in inflammatory processes. We also describe our recent findings regarding a specific S1P chaperone, apolipoprotein M, that anchors to high-density lipoprotein and contributes to shaping the endothelial-protective and anti-inflammatory properties of high-density lipoprotein.
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Affiliation(s)
- Hideru Obinata
- Gunma University Initiative for Advanced Research, Showa-machi, Maebashi, Gunma, Japan
| | - Timothy Hla
- Vascular Biology Program, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA, USA
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9
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Apolipoprotein M: Research Progress and Clinical Perspective. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1276:85-103. [PMID: 32705596 DOI: 10.1007/978-981-15-6082-8_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Apolipoprotein M (apoM) was first identified and characterized to the apolipoprotein family in 1999. Human apoM gene is located in a highly conserved segment in the major histocompatibility complex (MHC) class III locus on chromosome 6 and codes for an about 23 kDa protein that structurally belongs to the lipocalin superfamily. ApoM is selectively expressed in hepatocytes and in the tubular epithelium of kidney. In human plasma, apoM is mainly confined to the high-density lipoprotein (HDL) particles, but it may also occur in other lipoprotein classes, such as in the triglyceride-rich particles after fat intake. It has been demonstrated that apoM is critical for the formation of HDL, notably pre-beta HDL1. The antiatherogenic function of HDL is well established, and its ability to promote cholesterol efflux from foam cells in the atherosclerotic lesions is generally regarded as one of the key mechanisms behind this protective function. However, HDL could also display a variety of properties that may affect the complex atherosclerotic processes by other mechanisms, thus being involved in processes related to antioxidant defense, immune system, and systemic effects in septicemia, which may be partly contributed via its apolipoproteins and/or phospholipids. Moreover, it has been demonstrated that apoM functions as a natural carrier of sphingosin-1-phosphate (S1P) in vivo which may be related to its antiatherosclerotic and protective effects on endothelial cell barrier and anti-inflammatory properties. These may also provide a link between the diverse effects of HDL.
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10
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Abstract
Sphingosine-1-phosphate (S1P) is a lipidic mediator in mammals that functions either as a second messenger or as a ligand. In the latter case, it is transported by its HDL-associated apoM carrier and circulated in blood where it binds to specific S1P receptors on cell membranes and induces downstream reactions. Although S1P signaling pathways are essential for many biological processes, they are poorly understood at the molecular level. Here, the solved crystal structures of the S1P1 receptor were used to evaluate molecular dynamics (MD) simulations to generate greater detailed molecular insights into the mechanism of S1P signaling. The MD simulations provided observations at the coarse-grained and atomic levels indicating that S1P may access the receptor binding pocket directly from solvents. Lifting of the bulky N-terminal cap region of the receptor precedes initial S1P binding. Glu1213.29 guides S1P penetration, and together with Arg2927.34 is responsible for the stabilization of S1P in the binding pocket, which is consistent with experimental predictions. The complete binding of S1P is followed by receptor activation, wherein Trp2696.48 moves toward the transmembrane helix (TM) 7, resulting in the formation of an enhanced hydrogen bond network in the lower region of TM7. The distance between TM3 and TM6 is subsequently increased, resulting in the opening of the intracellular binding pocket that enables G protein binding. Further analysis of the force distribution network in the receptor yielded a detailed molecular understanding of the signal transmission network that is activated upon agonist binding.
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11
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The Structural Binding Mode of the Four Autotaxin Inhibitor Types that Differentially Affect Catalytic and Non-Catalytic Functions. Cancers (Basel) 2019; 11:cancers11101577. [PMID: 31623219 PMCID: PMC6826961 DOI: 10.3390/cancers11101577] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 09/27/2019] [Accepted: 10/08/2019] [Indexed: 12/20/2022] Open
Abstract
Autotaxin (ATX) is a secreted lysophospholipase D, catalysing the conversion of lysophosphatidylcholine (LPC) to bioactive lysophosphatidic acid (LPA). LPA acts through two families of G protein-coupled receptors (GPCRs) controlling key cellular responses, and it is implicated in many physiological processes and pathologies. ATX, therefore, has been established as an important drug target in the pharmaceutical industry. Structural and biochemical studies of ATX have shown that it has a bimetallic nucleophilic catalytic site, a substrate-binding (orthosteric) hydrophobic pocket that accommodates the lipid alkyl chain, and an allosteric tunnel that can accommodate various steroids and LPA. In this review, first, we revisit what is known about ATX-mediated catalysis, crucially in light of allosteric regulation. Then, we present the known ATX catalysis-independent functions, including binding to cell surface integrins and proteoglycans. Next, we analyse all crystal structures of ATX bound to inhibitors and present them based on the four inhibitor types that are established based on the binding to the orthosteric and/or the allosteric site. Finally, in light of these data we discuss how mechanistic differences might differentially modulate the activity of the ATX-LPA signalling axis, and clinical applications including cancer.
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12
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Bisgaard LS, Christoffersen C. Apolipoprotein M/sphingosine-1-phosphate: novel effects on lipids, inflammation and kidney biology. Curr Opin Lipidol 2019; 30:212-217. [PMID: 31008738 DOI: 10.1097/mol.0000000000000606] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE OF REVIEW In 2011, the crystal structure of apolipoprotein M (apoM) and its capacity to bind sphingosine-1-phosphate (S1P) was characterized. Since then, a variety of studies has increased our knowledge on apoM biology and functionality. From being an unknown and hardly significant player in overall metabolism, apoM has gained significant interest. RECENT FINDINGS Key discoveries in the last 2 years have indicated that the apoM/S1P complex has important roles in lipid metabolism (affecting triglyceride turnover), inflammation (a marker of severe sepsis and potentially providing anti-inflammatory signaling) and kidney biology (potential to protect against immunoglobulin A nephropathy). SUMMARY Several studies suggest a potential for apoM/S1P as biomarkers for inflammation, sepsis and nephropathy. Also, a novel chaperone is characterized and could have potential as a drug for treatment in inflammation and nephropathy.
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Affiliation(s)
| | - Christina Christoffersen
- Department of Clinical Biochemistry, Rigshospitalet
- Department of Clinical Biochemistry, Bispebjerg Hospital
- Department of Biomedical Science, University of Copenhagen, Copenhagen, Denmark
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13
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Liu M, Frej C, Langefeld CD, Divers J, Bowden DW, Carr JJ, Gebre AK, Xu J, Larsson B, Dahlbäck B, Freedman BI, Parks JS. Plasma apoM and S1P levels are inversely associated with mortality in African Americans with type 2 diabetes mellitus. J Lipid Res 2019; 60:1425-1431. [PMID: 31133557 DOI: 10.1194/jlr.p089409] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 04/27/2019] [Indexed: 12/21/2022] Open
Abstract
apoM is a minor HDL apolipoprotein and carrier for sphingosine-1-phosphate (S1P). HDL apoM and S1P concentrations are inversely associated with atherosclerosis progression in rodents. We evaluated associations between plasma concentrations of S1P, plasma concentrations of apoM, and HDL apoM levels with prevalent subclinical atherosclerosis and mortality in the African American-Diabetes Heart Study participants (N = 545). Associations between plasma S1P, plasma apoM, and HDL apoM with subclinical atherosclerosis and mortality were assessed using multivariate parametric, nonparametric, and Cox proportional hazards models. At baseline, participants' median (25th percentile, 75th percentile) age was 55 (49, 62) years old and their coronary artery calcium (CAC) mass score was 26.5 (0.0, 346.5). Plasma S1P, plasma apoM, and HDL apoM were not associated with CAC. After 64 (57.6, 70.3) months of follow-up, 81 deaths were recorded. Higher concentrations of plasma S1P [odds ratio (OR) = 0.14, P = 0.01] and plasma apoM (OR = 0.10, P = 0.02), but not HDL apoM (P = 0.89), were associated with lower mortality after adjusting for age, sex, statin use, CAC, kidney function, and albuminuria. We conclude that plasma S1P and apoM concentrations are inversely and independently associated with mortality, but not CAC, in African Americans with type 2 diabetes after accounting for conventional risk factors.
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Affiliation(s)
- Mingxia Liu
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC
| | - Cecilia Frej
- Department of Translational Medicine Skåne University Hospital, Lund University, Malmö, Sweden
| | - Carl D Langefeld
- Division of Public Health Sciences, Department of Biostatistics and Data Science Wake Forest School of Medicine, Winston-Salem, NC
| | - Jasmin Divers
- Division of Public Health Sciences, Department of Biostatistics and Data Science Wake Forest School of Medicine, Winston-Salem, NC
| | - Donald W Bowden
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC
| | - J Jeffrey Carr
- Department of Radiology Vanderbilt University Medical Center, Nashville, TN
| | - Abraham K Gebre
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC
| | - Jianzhao Xu
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC
| | - Benny Larsson
- Department of Clinical Chemistry Skåne University Hospital, Lund, Sweden
| | - Björn Dahlbäck
- Department of Translational Medicine Skåne University Hospital, Lund University, Malmö, Sweden
| | - Barry I Freedman
- Section on Nephrology, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC
| | - John S Parks
- Section on Molecular Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC .,Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC
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14
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Blaho VA, Chun J. 'Crystal' Clear? Lysophospholipid Receptor Structure Insights and Controversies. Trends Pharmacol Sci 2018; 39:953-966. [PMID: 30343728 PMCID: PMC6201317 DOI: 10.1016/j.tips.2018.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 08/11/2018] [Accepted: 08/27/2018] [Indexed: 12/29/2022]
Abstract
Lysophospholipids (LPLs), particularly sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA), are bioactive lipid modulators of cellular homeostasis and pathology. The discovery and characterization of five S1P- and six LPA-specific G protein-coupled receptors (GPCRs), S1P1-5 and LPA1-6, have expanded their known involvement in all mammalian physiological systems. Resolution of the S1P1, LPA1, and LPA6 crystal structures has fueled the growing interest in these receptors and their ligands as targets for pharmacological manipulation. In this review, we have attempted to provide an integrated overview of the three crystallized LPL GPCRs with biochemical and physiological structure-function data. Finally, we provide a novel discussion of how chaperones for LPLs may be considered when extrapolating crystallographic and computational data toward understanding actual biological interactions and phenotypes.
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Affiliation(s)
- Victoria A Blaho
- Sanford Burnham Prebys Medical Discovery Institute, Degenerative Diseases Program, La Jolla, CA 92037, USA.
| | - Jerold Chun
- Sanford Burnham Prebys Medical Discovery Institute, Degenerative Diseases Program, La Jolla, CA 92037, USA.
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15
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Kleuser B. Divergent Role of Sphingosine 1-Phosphate in Liver Health and Disease. Int J Mol Sci 2018; 19:ijms19030722. [PMID: 29510489 PMCID: PMC5877583 DOI: 10.3390/ijms19030722] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/08/2018] [Accepted: 02/26/2018] [Indexed: 12/11/2022] Open
Abstract
Two decades ago, sphingosine 1-phosphate (S1P) was discovered as a novel bioactive molecule that regulates a variety of cellular functions. The plethora of S1P-mediated effects is due to the fact that the sphingolipid not only modulates intracellular functions but also acts as a ligand of G protein-coupled receptors after secretion into the extracellular environment. In the plasma, S1P is found in high concentrations, modulating immune cell trafficking and vascular endothelial integrity. The liver is engaged in modulating the plasma S1P content, as it produces apolipoprotein M, which is a chaperone for the S1P transport. Moreover, the liver plays a substantial role in glucose and lipid homeostasis. A dysfunction of glucose and lipid metabolism is connected with the development of liver diseases such as hepatic insulin resistance, non-alcoholic fatty liver disease, or liver fibrosis. Recent studies indicate that S1P is involved in liver pathophysiology and contributes to the development of liver diseases. In this review, the current state of knowledge about S1P and its signaling in the liver is summarized with a specific focus on the dysregulation of S1P signaling in obesity-mediated liver diseases. Thus, the modulation of S1P signaling can be considered as a potential therapeutic target for the treatment of hepatic diseases.
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Affiliation(s)
- Burkhard Kleuser
- Department of Toxicology, Institute of Nutritional Science, Faculty of Mathematics and Natural Science, University of Potsdam, Arthur-Scheunert Allee 114-116, 14558 Nuthetal, Germany.
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16
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Zhang P, Gao J, Pu C, Zhang Y. Apolipoprotein status in type 2 diabetes mellitus and its complications (Review). Mol Med Rep 2017; 16:9279-9286. [PMID: 29152661 DOI: 10.3892/mmr.2017.7831] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 08/22/2017] [Indexed: 11/06/2022] Open
Abstract
Dyslipidaemia in type 2 diabetes mellitus (T2DM) is characterized by high plasma triglyceride concentrations, reduced high‑density lipoprotein concentrations and increased small density low‑density lipoprotein concentrations. Dyslipidaemia may lead to cardiovascular disease (CVD) and other complications. Apolipoproteins mainly comprise six species, apolipoprotein (apo)A, apoB, apoC, apoD, apoE and apoM, which are important components of plasma lipoproteins that carry lipids and stabilize the structure of lipoproteins. Complex metabolic disorders of apolipoproteins are present in T2DM, such as high plasma apoB, apoC‑II, apoC‑III and apoE concentrations, and low plasma apoA‑I and apoM concentrations, which are associated with dyslipidaemia and interrelated complications. Plasma concentrations of some apolipoproteins are also altered in T2DM with CVD or other complications. Several apolipoprotein polymorphisms are associated with diabetes susceptibility and/or lipid metabolism. The present review described the metabolic disorders of apolipoproteins in T2DM and its complications, and the relationship between each major apolipoprotein and T2DM, as well as the effects of apolipoprotein polymorphisms on diabetic susceptibility.
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Affiliation(s)
- Puhong Zhang
- Anhui Province Key Laboratory of Biological Macromolecules Research, Wannan Medical College, Wuhu, Anhui 241002, P.R. China
| | - Jialin Gao
- Department of Endocrinology and Genetic Metabolism, Yijishan Hospital of Wannan Medical College, Wuhu, Anhui 241002, P.R. China
| | - Chun Pu
- Clinical Laboratory, Yijishan Hospital of Wannan Medical College, Wuhu, Anhui 241002, P.R. China
| | - Yao Zhang
- Anhui Province Key Laboratory of Biological Macromolecules Research, Wannan Medical College, Wuhu, Anhui 241002, P.R. China
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17
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Hajny S, Christoffersen C. A Novel Perspective on the ApoM-S1P Axis, Highlighting the Metabolism of ApoM and Its Role in Liver Fibrosis and Neuroinflammation. Int J Mol Sci 2017; 18:ijms18081636. [PMID: 28749426 PMCID: PMC5578026 DOI: 10.3390/ijms18081636] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 07/18/2017] [Accepted: 07/25/2017] [Indexed: 02/07/2023] Open
Abstract
Hepatocytes, renal proximal tubule cells as well as the highly specialized endothelium of the blood brain barrier (BBB) express and secrete apolipoprotein M (apoM). ApoM is a typical lipocalin containing a hydrophobic binding pocket predominantly carrying Sphingosine-1-Phosphate (S1P). The small signaling molecule S1P is associated with several physiological as well as pathological pathways whereas the role of apoM is less explored. Hepatic apoM acts as a chaperone to transport S1P through the circulation and kidney derived apoM seems to play a role in S1P recovery to prevent urinal loss. Finally, polarized endothelial cells constituting the lining of the BBB express apoM and secrete the protein to the brain as well as to the blood compartment. The review will provide novel insights on apoM and S1P, and its role in hepatic fibrosis, neuroinflammation and BBB integrity.
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Affiliation(s)
- Stefan Hajny
- Department of Clinical Biochemistry, University Hospital of Copenhagen, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.
- Department of Biomedical Sciences, Faculty of Health and Science, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark.
| | - Christina Christoffersen
- Department of Clinical Biochemistry, University Hospital of Copenhagen, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.
- Department of Biomedical Sciences, Faculty of Health and Science, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark.
- Department of Cardiology, University Hospital of Copenhagen, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.
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18
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Rohrbach T, Maceyka M, Spiegel S. Sphingosine kinase and sphingosine-1-phosphate in liver pathobiology. Crit Rev Biochem Mol Biol 2017; 52:543-553. [PMID: 28618839 DOI: 10.1080/10409238.2017.1337706] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Over 20 years ago, sphingosine-1-phosphate (S1P) was discovered to be a bioactive signaling molecule. Subsequent studies later identified two related kinases, sphingosine kinase 1 and 2, which are responsible for the phosphorylation of sphingosine to S1P. Many stimuli increase sphingosine kinase activity and S1P production and secretion. Outside the cell, S1P can bind to and activate five S1P-specific G protein-coupled receptors (S1PR1-5) to regulate many important cellular and physiological processes in an autocrine or paracrine manner. S1P is found in high concentrations in the blood where it functions to control vascular integrity and trafficking of lymphocytes. Obesity increases blood S1P levels in humans and mice. With the world wide increase in obesity linked to consumption of high-fat, high-sugar diets, S1P is emerging as an accomplice in liver pathobiology, including acute liver failure, metabolic syndrome, control of blood lipid and glucose homeostasis, nonalcoholic fatty liver disease, and liver fibrosis. Here, we review recent research on the importance of sphingosine kinases, S1P, and S1PRs in liver pathobiology, with a focus on exciting insights for new therapeutic modalities that target S1P signaling axes for a variety of liver diseases.
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Affiliation(s)
- Timothy Rohrbach
- a Department of Biochemistry and Molecular Biology and the Massey Cancer Center , VCU School of Medicine , Richmond , VA , USA
| | - Michael Maceyka
- a Department of Biochemistry and Molecular Biology and the Massey Cancer Center , VCU School of Medicine , Richmond , VA , USA
| | - Sarah Spiegel
- a Department of Biochemistry and Molecular Biology and the Massey Cancer Center , VCU School of Medicine , Richmond , VA , USA
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19
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Zhang P, Gao J, Pu C, Feng G, Wang L, Huang L, Zhang Y. ApoM/HDL-C and apoM/apoA-I ratios are indicators of diabetic nephropathy in healthy controls and type 2 diabetes mellitus. Clin Chim Acta 2017; 466:31-37. [PMID: 28073663 DOI: 10.1016/j.cca.2017.01.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/05/2017] [Accepted: 01/06/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND Apolipoprotein M (apoM) concentrations were decreased in type 2 diabetes mellitus (T2DM). ApoM was selectively expressed in renal tubular epithelial cells. We investigated the changes in plasma apoM concentrations in diabetic nephropathy (DN) patients and the potential of apoM as a biomarker of DN. METHODS A total of 96 DN patients and 100 age- and sex-matched diabetic non-nephropathy (non-DN) patients and 110 healthy controls were included. All T2DM patients were divided into 3 groups according to urinary albumin excretion: normoalbuminuria (n=100), microalbuminuria (n=50) and macroalbuminuria (n=46). Plasma apoM concentrations were measured by enzyme-linked immunosorbent assay. RESULTS DN Patients had higher plasma apoM concentrations than those in non-DN patients (22.23±11.69 vs. 18.96±7.85ng/μl, P<0.05). In addition, microalbuminuria group showed higher plasma apoM concentrations than those in normoalbuminuria group (22.67±11.40 vs. 18.96±7.85ng/μl, P<0.05). The areas under curve (AUC) of apoM using a receiver-operating characteristic (ROC) curve analysis showed that plasma apoM concentrations were not indicators for identification of DN from healthy people (AUC=0.478, P=0.585) and from T2DM (AUC=0.563, P=0.125). DN patients had higher ratios of apoM/HDL-C and apoM/apoA1 than those in healthy controls and in non-DN patients. ApoM/HDL-C and apoM/apoA1 ratios could be used as indicators for identification of DN from healthy people (AUC=0.597, P=0.016; AUC=0.665, P=0.000, respectively) and from T2DM (AUC=0.580, P=0.050; AUC=0.601, P=0.015, respectively). CONCLUSIONS ApoM/HDL-C and apoM/apoA1 ratios could be used as indicators for identification of DN from healthy people and from T2DM patients.
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Affiliation(s)
- Puhong Zhang
- Anhui Province Key Laboratory of Biological Macro-molecules Research, Wannan Medical College, China; Department of Clinical Laboratory, The Second Affiliated Hospital of Wannan Medical College, China
| | - Jialin Gao
- Department of Endocrinology and Genetic Metabolism, Yijishan Hospital of Wannan Medical College, China; Anhui Province Key Laboratory of Biological Macro-molecules Research, Wannan Medical College, China
| | - Chun Pu
- Department of Clinical Laboratory, Yijishan Hospital of Wannan Medical College, China
| | - Gang Feng
- Department of Clinical Laboratory, Yijishan Hospital of Wannan Medical College, China
| | - Lizhuo Wang
- Department of Biochemistry and Molecular Biology, Wannan Medical College, China; Anhui Province Key Laboratory of Biological Macro-molecules Research, Wannan Medical College, China
| | - Lizhu Huang
- Department of Clinical Laboratory, Yijishan Hospital of Wannan Medical College, China
| | - Yao Zhang
- Department of Biochemistry and Molecular Biology, Wannan Medical College, China; Anhui Province Key Laboratory of Biological Macro-molecules Research, Wannan Medical College, China.
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