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Zhang X, Lyu D, Li S, Xiao H, Qiu Y, Xu K, Chen N, Deng L, Huang H, Wu R. Discovery of a SUCNR1 antagonist for potential treatment of diabetic nephropathy: In silico and in vitro studies. Int J Biol Macromol 2024; 268:131898. [PMID: 38677680 DOI: 10.1016/j.ijbiomac.2024.131898] [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: 03/10/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 04/29/2024]
Abstract
Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus. Succinate Receptor 1 (SUCNR1), a member of the G-protein-coupled receptor (GPCR) family, represents a potential target for treatment of DN. Here, utilizing multi-strategy in silico virtual screening methods containing AlphaFold2 modelling, molecular dynamics (MD) simulation, ligand-based pharmacophore screening, molecular docking and machine learning-based similarity clustering, we successfully identified a novel antagonist of SUCNR1, AK-968/12117473 (Cpd3). Through extensive in vitro experiments, including dual-luciferase reporter assay, cellular thermal shift assay, immunofluorescence, and western blotting, we substantiated that Cpd3 could specifically target SUCNR1, inhibit the activation of NF-κB pathway, and ameliorate epithelial-mesenchymal transition (EMT) and extracellular matrix (ECM) deposition in renal tubular epithelial cells (NRK-52E) under high glucose conditions. Further in silico simulations revealed the molecular basis of the SUCNR1-Cpd3 interaction, and the in vitro metabolic stability assay indicated favorable drug-like pharmacokinetic properties of Cpd3. This work not only successfully pinpointed Cpd3 as a specific antagonist of SUCNR1 to serve as a promising candidate in the realm of therapeutic interventions for DN, but also provides a paradigm of dry-wet combined discovery strategies for GPCR-based therapeutics.
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Affiliation(s)
- Xuting Zhang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; Guangzhou Hospital of Integrated Traditional and Western Medicine, Guangzhou 510801, China
| | - Dongxin Lyu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Shanshan Li
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Haiming Xiao
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yufan Qiu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Kangwei Xu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Nianhang Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Li Deng
- College of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China.
| | - Heqing Huang
- Guangzhou Hospital of Integrated Traditional and Western Medicine, Guangzhou 510801, China.
| | - Ruibo Wu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
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2
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Fernández-Veledo S, Marsal-Beltran A, Vendrell J. Type 2 diabetes and succinate: unmasking an age-old molecule. Diabetologia 2024; 67:430-442. [PMID: 38182909 PMCID: PMC10844351 DOI: 10.1007/s00125-023-06063-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 10/18/2023] [Indexed: 01/07/2024]
Abstract
Beyond their conventional roles in intracellular energy production, some traditional metabolites also function as extracellular messengers that activate cell-surface G-protein-coupled receptors (GPCRs) akin to hormones and neurotransmitters. These signalling metabolites, often derived from nutrients, the gut microbiota or the host's intermediary metabolism, are now acknowledged as key regulators of various metabolic and immune responses. This review delves into the multi-dimensional aspects of succinate, a dual metabolite with roots in both the mitochondria and microbiome. It also connects the dots between succinate's role in the Krebs cycle, mitochondrial respiration, and its double-edge function as a signalling transmitter within and outside the cell. We aim to provide an overview of the role of the succinate-succinate receptor 1 (SUCNR1) axis in diabetes, discussing the potential use of succinate as a biomarker and the novel prospect of targeting SUCNR1 to manage complications associated with diabetes. We further propose strategies to manipulate the succinate-SUCNR1 axis for better diabetes management; this includes pharmacological modulation of SUCNR1 and innovative approaches to manage succinate concentrations, such as succinate administration and indirect strategies, like microbiota modulation. The dual nature of succinate, both in terms of origins and roles, offers a rich landscape for understanding the intricate connections within metabolic diseases, like diabetes, and indicates promising pathways for developing new therapeutic strategies.
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Affiliation(s)
- Sonia Fernández-Veledo
- Hospital Universitari Joan XXIII de Tarragona, Institut d'Investigació Sanitària Pere Virgili (IISPV)-CERCA, Tarragona, Spain.
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM)-Instituto de Salud Carlos III (ISCIII), Madrid, Spain.
- Universitat Rovira I Virgili (URV), Reus, Spain.
| | - Anna Marsal-Beltran
- Hospital Universitari Joan XXIII de Tarragona, Institut d'Investigació Sanitària Pere Virgili (IISPV)-CERCA, Tarragona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM)-Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Universitat Rovira I Virgili (URV), Reus, Spain
| | - Joan Vendrell
- Hospital Universitari Joan XXIII de Tarragona, Institut d'Investigació Sanitària Pere Virgili (IISPV)-CERCA, Tarragona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM)-Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Universitat Rovira I Virgili (URV), Reus, Spain
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3
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Zhang L, Buonfiglio F, Fieß A, Pfeiffer N, Gericke A. Retinopathy of Prematurity-Targeting Hypoxic and Redox Signaling Pathways. Antioxidants (Basel) 2024; 13:148. [PMID: 38397746 PMCID: PMC10885953 DOI: 10.3390/antiox13020148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 01/19/2024] [Accepted: 01/21/2024] [Indexed: 02/25/2024] Open
Abstract
Retinopathy of prematurity (ROP) is a proliferative vascular ailment affecting the retina. It is the main risk factor for visual impairment and blindness in infants and young children worldwide. If left undiagnosed and untreated, it can progress to retinal detachment and severe visual impairment. Geographical variations in ROP epidemiology have emerged over recent decades, attributable to differing levels of care provided to preterm infants across countries and regions. Our understanding of the causes of ROP, screening, diagnosis, treatment, and associated risk factors continues to advance. This review article aims to present the pathophysiological mechanisms of ROP, including its treatment. Specifically, it delves into the latest cutting-edge treatment approaches targeting hypoxia and redox signaling pathways for this condition.
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Affiliation(s)
| | | | | | | | - Adrian Gericke
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany; (L.Z.); (F.B.); (A.F.); (N.P.)
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4
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Choi AJ, Hefley BS, Nicholas SE, Cunningham RL, Karamichos D. Novel Correlation between TGF-β1/-β3 and Hormone Receptors in the Human Corneal Stroma. Int J Mol Sci 2023; 24:13635. [PMID: 37686439 PMCID: PMC10487450 DOI: 10.3390/ijms241713635] [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: 07/15/2023] [Revised: 08/22/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023] Open
Abstract
This study investigated the interplay between transforming growth factor beta (TGF-β1/T1 and TGF-β3/T3), and sex hormone receptors using our 3D in vitro cornea stroma model. Primary human corneal fibroblasts (HCFs) from healthy donors were plated in transwells at 106 cells/well and cultured for four weeks. HCFs were supplemented with stable vitamin C (VitC) and stimulated with T1 or T3. 3D construct proteins were analyzed for the androgen receptor (AR), progesterone receptor (PR), estrogen receptor alpha (ERα) and beta (ERβ), luteinizing hormone receptor (LHR), follicle-stimulating hormone receptor (FSHR), gonadotropin-releasing hormone receptor (GnRHR), KiSS1-derived peptide receptor (KiSS1R/GPR54), and follicle-stimulating hormone subunit beta (FSH-B). In female constructs, T1 significantly upregulated AR, PR, ERα, FSHR, GnRHR, and KiSS1R. In male constructs, T1 significantly downregulated FSHR and FSH-B and significantly upregulated ERα, ERβ, and GnRHR. T3 caused significant upregulation in expressions PR, ERα, ERβ, LHR, FSHR, and GNRHR in female constructs, and significant downregulation of AR, ERα, and FSHR in male constructs. Semi-quantitative Western blot findings present the interplay between sex hormone receptors and TGF-β isoforms in the corneal stroma, which is influenced by sex as a biological variable (SABV). Additional studies are warranted to fully delineate their interactions and signaling mechanisms.
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Affiliation(s)
- Alexander J. Choi
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (A.J.C.); (B.S.H.); (S.E.N.)
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107, USA;
| | - Brenna S. Hefley
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (A.J.C.); (B.S.H.); (S.E.N.)
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107, USA;
| | - Sarah E. Nicholas
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (A.J.C.); (B.S.H.); (S.E.N.)
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107, USA;
| | - Rebecca L. Cunningham
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107, USA;
| | - Dimitrios Karamichos
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (A.J.C.); (B.S.H.); (S.E.N.)
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107, USA;
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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Benavente-Perez A. Evidence of vascular involvement in myopia: a review. Front Med (Lausanne) 2023; 10:1112996. [PMID: 37275358 PMCID: PMC10232763 DOI: 10.3389/fmed.2023.1112996] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 05/02/2023] [Indexed: 06/07/2023] Open
Abstract
The benign public perception of myopia (nearsightedness) as a visual inconvenience masks the severity of its sight-threatening consequences. Myopia is a significant risk factor for posterior pole conditions such as maculopathy, choroidal neovascularization and glaucoma, all of which have a vascular component. These associations strongly suggest that myopic eyes might experience vascular alterations prior to the development of complications. Myopic eyes are out of focus because they are larger in size, which in turn affects their overall structure and function, including those of the vascular beds. By reviewing the vascular changes that characterize myopia, this review aims to provide an understanding of the gross, cellular and molecular alterations identified at the structural and functional levels with the goal to provide an understanding of the latest evidence in the field of experimental and clinical myopia vascular research. From the evidence presented, we hypothesize that the interaction between excessive myopic eye growth and vascular alterations are tipping-points for the development of sight-threatening changes.
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Fevereiro-Martins M, Marques-Neves C, Guimarães H, Bicho M. Retinopathy of prematurity: A review of pathophysiology and signaling pathways. Surv Ophthalmol 2023; 68:175-210. [PMID: 36427559 DOI: 10.1016/j.survophthal.2022.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022]
Abstract
Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina and a leading cause of visual impairment and childhood blindness worldwide. The disease is characterized by an early stage of retinal microvascular degeneration, followed by neovascularization that can lead to subsequent retinal detachment and permanent visual loss. Several factors play a key role during the different pathological stages of the disease. Oxidative and nitrosative stress and inflammatory processes are important contributors to the early stage of ROP. Nitric oxide synthase and arginase play important roles in ischemia/reperfusion-induced neurovascular degeneration. Destructive neovascularization is driven by mediators of the hypoxia-inducible factor pathway, such as vascular endothelial growth factor and metabolic factors (succinate). The extracellular matrix is involved in hypoxia-induced retinal neovascularization. Vasorepulsive molecules (semaphorin 3A) intervene preventing the revascularization of the avascular zone. This review focuses on current concepts about signaling pathways and their mediators, involved in the pathogenesis of ROP, highlighting new potentially preventive and therapeutic modalities. A better understanding of the intricate molecular mechanisms underlying the pathogenesis of ROP should allow the development of more effective and targeted therapeutic agents to reduce aberrant vasoproliferation and facilitate physiological retinal vascular development.
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Affiliation(s)
- Mariza Fevereiro-Martins
- Laboratório de Genética and Grupo Ecogenética e Saúde Humana, Instituto de Saúde Ambiental, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Investigação Científica Bento da Rocha Cabral, Lisboa, Portugal; Departamento de Oftalmologia, Hospital Cuf Descobertas, Lisboa, Portugal.
| | - Carlos Marques-Neves
- Centro de Estudos das Ci.¼ncias da Visão, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Grupo Ecogenética e Saúde Humana, Instituto de Saúde Ambiental, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
| | - Hercília Guimarães
- Departamento de Ginecologia-Obstetrícia e Pediatria, Faculdade de Medicina, Universidade do Porto, Porto, Portugal.
| | - Manuel Bicho
- Laboratório de Genética and Grupo Ecogenética e Saúde Humana, Instituto de Saúde Ambiental, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Investigação Científica Bento da Rocha Cabral, Lisboa, Portugal.
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7
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Zhang S, Liang Y, Li L, Chen Y, Wu P, Wei D. Succinate: A Novel Mediator to Promote Atherosclerotic Lesion Progression. DNA Cell Biol 2022; 41:285-291. [PMID: 35138943 DOI: 10.1089/dna.2021.0345] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Succinate is an important intermediate product of mitochondrial energy metabolism. Recent studies revealed that beyond its known traditional metabolic functions, succinate plays important roles in signal transduction, immunity, inflammation, and posttranslational modification. Recent studies showed that patients and mouse models with cardiovascular disease have high levels of serum succinate and succinate accumulation. Atherosclerosis (As) is the pathological basis of cardiovascular and peripheral vascular diseases, such as coronary heart disease, cerebral infarction, and peripheral vascular disease, and is a major factor affecting human health. This article reviews the progression of succinate in As diseases and its underlying mechanisms.
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Affiliation(s)
- Shulei Zhang
- Key Laboratory for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, University of South China, Hengyang, China
| | - Yamin Liang
- Key Laboratory for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, University of South China, Hengyang, China
| | - Lu Li
- Key Laboratory for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, University of South China, Hengyang, China
| | - Yanmei Chen
- Key Laboratory for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, University of South China, Hengyang, China
| | - Peng Wu
- Key Laboratory for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, University of South China, Hengyang, China
| | - Dangheng Wei
- Key Laboratory for Arteriosclerology of Hunan Province, Institute of Cardiovascular Disease, Hunan International Scientific and Technological Cooperation Base of Arteriosclerotic Disease, University of South China, Hengyang, China
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8
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Terra X, Ceperuelo-Mallafré V, Merma C, Benaiges E, Bosch R, Castillo P, Flores JC, León X, Valduvieco I, Basté N, Cámara M, Lejeune M, Gumà J, Vendrell J, Vilaseca I, Fernández-Veledo S, Avilés-Jurado FX. Succinate Pathway in Head and Neck Squamous Cell Carcinoma: Potential as a Diagnostic and Prognostic Marker. Cancers (Basel) 2021; 13:cancers13071653. [PMID: 33916314 PMCID: PMC8037494 DOI: 10.3390/cancers13071653] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/23/2021] [Accepted: 03/24/2021] [Indexed: 12/14/2022] Open
Abstract
Simple Summary Emerging evidence points to succinate as an important oncometabolite in cancer development; however, the contribution of the succinate-SUCNR1 axis to cancer progression remains unclear. Head and neck squamous cell carcinoma (HNSCC) is associated with disease and treatment-related morbidity so there is an urgent need for innovation in treatment and diagnosis practices. Our aim was to evaluate the potential of the succinate-related pathway as a diagnostic and prognostic biomarker in HNSCC. The circulating succinate levels are increased in HNSCC, being a potential noninvasive biomarker for HNSCC diagnosis. Moreover, the succinate receptor (SUCNR1) and genes related to succinate metabolism, which are predominantly expressed in the tumoral mucosa as compared with healthy tissue, are positively associated with plasma succinate. Remarkably, we found that SUCNR1 and SDHA expression levels predict prognosis. Abstract Head and neck squamous cell carcinoma (HNSCC) is characterized by high rates of mortality and treatment-related morbidity, underscoring the urgent need for innovative and safe treatment strategies and diagnosis practices. Mitochondrial dysfunction is a hallmark of cancer and can lead to the accumulation of tricarboxylic acid cycle intermediates, such as succinate, which function as oncometabolites. In addition to its role in cancer development through epigenetic events, succinate is an extracellular signal transducer that modulates immune response, angiogenesis and cell invasion by activating its cognate receptor SUCNR1. Here, we explored the potential value of the circulating succinate and related genes in HNSCC diagnosis and prognosis. We determined the succinate levels in the serum of 66 pathologically confirmed, untreated patients with HNSCC and 20 healthy controls. We also surveyed the expression of the genes related to succinate metabolism and signaling in tumoral and nontumoral adjacent tissue and in normal mucosa from 50 patients. Finally, we performed immunohistochemical analysis of SUCNR1 in mucosal samples. The results showed that the circulating levels of succinate were higher in patients with HNSCC than in the healthy controls. Additionally, the expression of SUCNR1, HIF-1α, succinate dehydrogenase (SDH) A, and SDHB was higher in the tumor tissue than in the matched normal mucosa. Consistent with this, immunohistochemical analysis revealed an increase in SUCNR1 protein expression in tumoral and nontumoral adjacent tissue. High SUCNR1 and SDHA expression levels were associated with poor locoregional control, and the locoregional recurrence-free survival rate was significantly lower in patients with high SUCNR1 and SDHA expression than in their peers with lower levels (77.1% [95% CI: 48.9–100.0] vs. 16.7% [95% CI: 0.0–44.4], p = 0.018). Thus, the circulating succinate levels are elevated in HNSCC and high SUCNR1/SDHA expression predicts poor locoregional disease-free survival, identifying this oncometabolite as a potentially valuable noninvasive biomarker for HNSCC diagnosis and prognosis.
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Affiliation(s)
- Ximena Terra
- MoBioFood Research Group, Biochemistry and Biotechnology Department, Universitat Rovira i Virgili, Campus Sescel·lades, 43007 Tarragona, Spain;
| | - Victoria Ceperuelo-Mallafré
- Department of Endocrinology and Nutrition, Institut d’Investigació Sanitària Pere Virgili (IISPV), Hospital Universitari de Tarragona Joan XXIII, 43005 Tarragona, Spain; (V.C.-M.); (E.B.); (J.V.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), 28029 Madrid, Spain
| | - Carla Merma
- Otorhinolaryngology Head-Neck Surgery Department, Hospital Universitari de Tarragona Joan XXIII, Insitut d’Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, 43005 Tarragona, Spain; (C.M.); (J.C.F.)
| | - Ester Benaiges
- Department of Endocrinology and Nutrition, Institut d’Investigació Sanitària Pere Virgili (IISPV), Hospital Universitari de Tarragona Joan XXIII, 43005 Tarragona, Spain; (V.C.-M.); (E.B.); (J.V.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), 28029 Madrid, Spain
- School of Medicine, Universitat Rovira i Virgili, 43201 Reus, Spain
| | - Ramon Bosch
- Pathology Department, Plataforma de Estudios Histológicos, Citológicos y de Digitalización, Hospital de Tortosa Verge de la Cinta, Institut d’Investigació Sanitària Pere Virgili (IISPV), URV, 43500 Tortosa, Spain; (R.B.); (M.L.)
| | - Paola Castillo
- Pathology Department, Hospital Clínic de Barcelona, IDIBAPS, 08036 Barcelona, Spain;
| | - Joan Carles Flores
- Otorhinolaryngology Head-Neck Surgery Department, Hospital Universitari de Tarragona Joan XXIII, Insitut d’Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, 43005 Tarragona, Spain; (C.M.); (J.C.F.)
| | - Xavier León
- Otorhinolaryngology Head-Neck Surgery Department, Hospital de la Santa Creu i Sant Pau and Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN, MICINN, ISCIII), Universitat Autònoma de Barcelona, 08041 Barcelona, Spain;
| | - Izaskun Valduvieco
- Radiation Oncology Department, Hospital Clínic de Barcelona, 08036 Barcelona, Spain;
| | - Neus Basté
- Oncology Department, IDIBAPS, Hospital Clínic de Barcelona, 08036 Barcelona, Spain;
| | - Marina Cámara
- Maxillofacial Department, Hospital Clínic de Barcelona, 08036 Barcelona, Spain;
| | - Marylène Lejeune
- Pathology Department, Plataforma de Estudios Histológicos, Citológicos y de Digitalización, Hospital de Tortosa Verge de la Cinta, Institut d’Investigació Sanitària Pere Virgili (IISPV), URV, 43500 Tortosa, Spain; (R.B.); (M.L.)
| | - Josep Gumà
- Oncology Department, Institut d’Investigació Sanitària Pere Virgili (IISPV), Hospital Sant Joan de Reus, 43204 Reus, Spain;
| | - Joan Vendrell
- Department of Endocrinology and Nutrition, Institut d’Investigació Sanitària Pere Virgili (IISPV), Hospital Universitari de Tarragona Joan XXIII, 43005 Tarragona, Spain; (V.C.-M.); (E.B.); (J.V.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), 28029 Madrid, Spain
- School of Medicine, Universitat Rovira i Virgili, 43201 Reus, Spain
| | - Isabel Vilaseca
- Otorhinolaryngology Department, UB, IDIBAPS, Hospital Clínic de Barcelona, 08036 Barcelona, Spain;
- Head Neck Clínic, Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR), 2017-SGR-01581 Barcelona, Spain
| | - Sonia Fernández-Veledo
- Department of Endocrinology and Nutrition, Institut d’Investigació Sanitària Pere Virgili (IISPV), Hospital Universitari de Tarragona Joan XXIII, 43005 Tarragona, Spain; (V.C.-M.); (E.B.); (J.V.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), 28029 Madrid, Spain
- Correspondence: (S.F.-V.); (F.X.A.-J.)
| | - Francesc Xavier Avilés-Jurado
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), 28029 Madrid, Spain
- Otorhinolaryngology Department, UB, IDIBAPS, Hospital Clínic de Barcelona, 08036 Barcelona, Spain;
- Head Neck Clínic, Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR), 2017-SGR-01581 Barcelona, Spain
- Correspondence: (S.F.-V.); (F.X.A.-J.)
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González-Casanova J, Schmachtenberg O, Martínez AD, Sanchez HA, Harcha PA, Rojas-Gomez D. An Update on Connexin Gap Junction and Hemichannels in Diabetic Retinopathy. Int J Mol Sci 2021; 22:ijms22063194. [PMID: 33801118 PMCID: PMC8004116 DOI: 10.3390/ijms22063194] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/06/2021] [Accepted: 03/10/2021] [Indexed: 01/10/2023] Open
Abstract
Diabetic retinopathy (DR) is one of the main causes of vision loss in the working age population. It is characterized by a progressive deterioration of the retinal microvasculature, caused by long-term metabolic alterations inherent to diabetes, leading to a progressive loss of retinal integrity and function. The mammalian retina presents an orderly layered structure that executes initial but complex visual processing and analysis. Gap junction channels (GJC) forming electrical synapses are present in each retinal layer and contribute to the communication between different cell types. In addition, connexin hemichannels (HCs) have emerged as relevant players that influence diverse physiological and pathological processes in the retina. This article highlights the impact of diabetic conditions on GJC and HCs physiology and their involvement in DR pathogenesis. Microvascular damage and concomitant loss of endothelial cells and pericytes are related to alterations in gap junction intercellular communication (GJIC) and decreased connexin 43 (Cx43) expression. On the other hand, it has been shown that the expression and activity of HCs are upregulated in DR, becoming a key element in the establishment of proinflammatory conditions that emerge during hyperglycemia. Hence, novel connexin HCs blockers or drugs to enhance GJIC are promising tools for the development of pharmacological interventions for diabetic retinopathy, and initial in vitro and in vivo studies have shown favorable results in this regard.
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Affiliation(s)
- Jorge González-Casanova
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago 8910060, Chile;
| | - Oliver Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Biología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile;
| | - Agustín D. Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (A.D.M.); (H.A.S.); (P.A.H.)
| | - Helmuth A. Sanchez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (A.D.M.); (H.A.S.); (P.A.H.)
| | - Paloma A. Harcha
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile; (A.D.M.); (H.A.S.); (P.A.H.)
| | - Diana Rojas-Gomez
- Escuela de Nutrición y Dietética, Facultad de Medicina, Universidad Andres Bello, Santiago 8370146, Chile
- Correspondence: ; Tel.: +56-2-26618559
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10
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Forrester JV, Kuffova L, Delibegovic M. The Role of Inflammation in Diabetic Retinopathy. Front Immunol 2020; 11:583687. [PMID: 33240272 PMCID: PMC7677305 DOI: 10.3389/fimmu.2020.583687] [Citation(s) in RCA: 172] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/21/2020] [Indexed: 12/14/2022] Open
Abstract
Inflammation is central to pathogenic processes in diabetes mellitus and the metabolic syndrome and particularly implicates innate immunity in the development of complications. Inflammation is a primary event in Type 1 diabetes where infectious (viral) and/or autoimmune processes initiate disease; in contrast, chronic inflammation is typical in Type 2 diabetes and is considered a sequel to increasing insulin resistance and disturbed glucose metabolism. Diabetic retinopathy (DR) is perceived as a vascular and neurodegenerative disease which occurs after some years of poorly controlled diabetes. However, many of the clinical features of DR are late events and reflect the nature of the retinal architecture and its cellular composition. Retinal microvascular disease is, in fact, an early event pathogenetically, induced by low grade, persistent leukocyte activation which causes repeated episodes of capillary occlusion and, progressive, attritional retinal ischemia. The later, overt clinical signs of DR are a consequence of the retinal ischemia. Metabolic dysregulation involving both lipid and glucose metabolism may lead to leukocyte activation. On a molecular level, we have shown that macrophage-restricted protein tyrosine phosphatase 1B (PTP1B) is a key regulator of inflammation in the metabolic syndrome involving insulin resistance and it is possible that PTP1B dysregulation may underlie retinal microvascular disease. We have also shown that adherent CCR5+CD11b+ monocyte macrophages appear to be selectively involved in retinal microvascular occlusion. In this review, we discuss the relationship between early leukocyte activation and the later features of DR, common pathogenetic processes between diabetic microvascular disease and other vascular retinopathies, the mechanisms whereby leukocyte activation is induced in hyperglycemia and dyslipidemia, the signaling mechanisms involved in diabetic microvascular disease, and possible interventions which may prevent these retinopathies. We also address a possible role for adaptive immunity in DR. Although significant improvements in treatment of DR have been made with intravitreal anti-VEGF therapy, a sizeable proportion of patients, particularly with sight-threatening macular edema, fail to respond. Alternative therapies targeting inflammatory processes may offer an advantage.
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Affiliation(s)
- John V Forrester
- Institute of Medical Sciences, University of Aberdeen, Scotland, United Kingdom
| | - Lucia Kuffova
- Institute of Medical Sciences, University of Aberdeen, Scotland, United Kingdom.,Eye Clinic, Aberdeen Royal Infirmary, Aberdeen, United Kingdom
| | - Mirela Delibegovic
- Institute of Medical Sciences, University of Aberdeen, Scotland, United Kingdom
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11
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Webb M, Sideris DP. Intimate Relations-Mitochondria and Ageing. Int J Mol Sci 2020; 21:ijms21207580. [PMID: 33066461 PMCID: PMC7589147 DOI: 10.3390/ijms21207580] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 12/14/2022] Open
Abstract
Mitochondrial dysfunction is associated with ageing, but the detailed causal relationship between the two is still unclear. We review the major phenomenological manifestations of mitochondrial age-related dysfunction including biochemical, regulatory and energetic features. We conclude that the complexity of these processes and their inter-relationships are still not fully understood and at this point it seems unlikely that a single linear cause and effect relationship between any specific aspect of mitochondrial biology and ageing can be established in either direction.
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Affiliation(s)
- Michael Webb
- Mitobridge Inc., an Astellas Company, 1030 Massachusetts Ave, Cambridge, MA 02138, USA
| | - Dionisia P Sideris
- Mitobridge Inc., an Astellas Company, 1030 Massachusetts Ave, Cambridge, MA 02138, USA
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12
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Herat LY, Ward NC, Magno AL, Rakoczy EP, Kiuchi MG, Schlaich MP, Matthews VB. Sodium glucose co-transporter 2 inhibition reduces succinate levels in diabetic mice. World J Gastroenterol 2020; 26:3225-3235. [PMID: 32684737 PMCID: PMC7336319 DOI: 10.3748/wjg.v26.i23.3225] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/19/2020] [Accepted: 06/09/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Type 1 diabetes (T1D) is associated with major chronic microvascular complications which contribute significantly to diabetes associated morbidity. The protein primarily responsible for glucose reabsorption in the kidney is sodium glucose co-transporter 2 (SGLT2). Presently, SGLT2 inhibitors are widely used in diabetic patients to improve blood glucose levels and prevent cardiovascular and renal complications. Given the broad therapeutic application of SGLT2 inhibitors, we hypothesised that SGLT2 inhibition may exert its protective effects via alterations of the gut microbiome and tested this in a type 1 diabetic mouse model of diabetic retinopathy.
AIM To determine whether the treatment with two independent SGLT2 inhibitors affects gut health in a type 1 diabetic mouse model.
METHODS The SGLT2 inhibitors empagliflozin or dapagliflozin (25 mg/kg/d) or vehicle dimethylsulfoxide (DMSO) were administered to C57BL/6J, Akita, Kimba and Akimba mice at 10 wk of age for 8 wk via their drinking water. Serum samples were collected and the concentration of succinate and the short chain fatty acid (SCFA) butyric acid was measured using gas chromatography-mass spectrometry. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the concentration of insulin and leptin. Furthermore, the norepinephrine content in kidney tissue was determined using ELISA. Pancreatic tissue was collected and stained with haematoxylin and eosin and analysed using brightfield microscopy.
RESULTS Due to the presence of the Akita allele, both Akita and Akimba mice showed a reduction in insulin production compared to C57BL/6J and Kimba mice. Furthermore, Akita mice also showed the presence of apoptotic bodies within the pancreatic islets. The acinar cells of Akita and Akimba mice showed swelling which is indicative of acute injury or pancreatitis. After 8 wk of SGLT2 inhibition with dapagliflozin, the intermediate metabolite of gut metabolism known as succinate was significantly reduced in Akimba mice when compared to DMSO treated mice. In addition, empagliflozin resulted in suppression of succinate levels in Akimba mice. The beneficial SCFA known as butyric acid was significantly increased in Akita mice after treatment with dapagliflozin when compared to vehicle treated mice. The norepinephrine content in the kidney was significantly reduced with both dapagliflozin and empagliflozin therapy in Akita mice and was significantly reduced in Akimba mice treated with empagliflozin. In non-diabetic C57BL/6J and Kimba mice, serum leptin levels were significantly reduced after dapagliflozin therapy.
CONCLUSION The inhibition of SGLT2 reduces the intermediate metabolite succinate, increases SCFA butyric acid levels and reduces norepinephrine content in mouse models of T1D. Collectively, these improvements may represent an important mechanism underlying the potential benefits of SGLT2 inhibition in T1D and its complications.
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Affiliation(s)
- Lakshini Y Herat
- School of Biomedical Sciences, Dobney Hypertension Centre, Royal Perth Hospital Unit, University of Western Australia, Perth 6000, Australia
| | - Natalie C Ward
- Faculty of Health and Medical Sciences, University of Western Australia, Crawley 6009, Australia
- Faculty of Health Sciences, School of Public Health, Curtin University, Bentley 6102, Australia
| | - Aaron L Magno
- Research Centre, Royal Perth Hospital, Perth 6000, Australia
| | - Elizabeth P Rakoczy
- Department of Molecular Ophthalmology, University of Western Australia, Crawley 6009, Australia
| | - Marcio G Kiuchi
- Dobney Hypertension Centre, School of Medicine, Royal Perth Hospital Unit, University of Western Australia, Perth 6000, Australia
| | - Markus P Schlaich
- Dobney Hypertension Centre, School of Medicine, Royal Perth Hospital Unit, University of Western Australia, Perth 6000, Australia
- Department of Cardiology and Department of Nephrology, Royal Perth Hospital, Perth 6000, Australia
| | - Vance B Matthews
- School of Biomedical Sciences, Dobney Hypertension Centre, Royal Perth Hospital Unit, University of Western Australia, Perth 6000, Australia
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13
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Inhibition of GPR91 Reduces Inflammatory Mediators Involved in Active Labor in Myometrium. Mediators Inflamm 2020; 2020:6454282. [PMID: 32377163 PMCID: PMC7180404 DOI: 10.1155/2020/6454282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 02/25/2020] [Accepted: 03/12/2020] [Indexed: 12/29/2022] Open
Abstract
Results GPR91 mRNA expression was significantly higher in myometrium from women during term spontaneous labor compared to no labor. Likewise, in mice, GPR91 mRNA expression was significantly upregulated in myometrium during inflammation-induced preterm labor compared to preterm no labor. In myometrial cells, IL1B and TNF significantly increased GPR91 mRNA expression. Knockdown of GPR91 by siRNA in myometrial cells significantly suppressed the secretion and/or expression of IL1B- and TNF-induced proinflammatory cytokines (GM-CSF, IL1A, IL1B, and IL6) and chemokines (CXCL8 and CCL2), myometrial contractility (expression of the contraction-associated proteins PTGFR and CX43, secretion of the uterotonic PGF2α, and in situ collagen gel contraction), and the transcription factor NF-κB. Conclusion Our findings demonstrate that GPR91 is involved in the genesis of proinflammatory and prolabor mediators induced by IL1B or TNF and collectively suggest that GPR91 may contribute to augmentation of the labor processes.
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14
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Potilinski MC, Lorenc V, Perisset S, Gallo JE. Mechanisms behind Retinal Ganglion Cell Loss in Diabetes and Therapeutic Approach. Int J Mol Sci 2020; 21:ijms21072351. [PMID: 32231131 PMCID: PMC7177797 DOI: 10.3390/ijms21072351] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/20/2020] [Accepted: 02/20/2020] [Indexed: 02/07/2023] Open
Abstract
Diabetes produces several changes in the body triggered by high glycemia. Some of these changes include altered metabolism, structural changes in blood vessels and chronic inflammation. The eye and particularly the retinal ganglion cells (RGCs) are not spared, and the changes eventually lead to cell loss and visual function impairment. Understanding the mechanisms resulting in RGC damage and loss from diabetic retinopathy is essential to find an effective treatment. This review focuses mainly on the signaling pathways and molecules involved in RGC loss and the potential therapeutic approaches for the prevention of this cell death. Throughout the manuscript it became evident that multiple factors of different kind are responsible for RGC damage. This shows that new therapeutic agents targeting several factors at the same time are needed. Alpha-1 antitrypsin as an anti-inflammatory agent may become a suitable option for the treatment of RGC loss because of its beneficial interaction with several signaling pathways involved in RGC injury and inflammation. In conclusion, alpha-1 antitrypsin may become a potential therapeutic agent for the treatment of RGC loss and processes behind diabetic retinopathy.
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Affiliation(s)
- María Constanza Potilinski
- Instituto de Investigaciones en Medicina Traslacional (IIMT), Facultad de Ciencias Biomedicas, Universidad Austral-CONICET, Av. J.D. Perón 1500, 1629 Pilar, Buenos Aires, Argentina; (M.C.P.); (V.L.); (S.P.)
| | - Valeria Lorenc
- Instituto de Investigaciones en Medicina Traslacional (IIMT), Facultad de Ciencias Biomedicas, Universidad Austral-CONICET, Av. J.D. Perón 1500, 1629 Pilar, Buenos Aires, Argentina; (M.C.P.); (V.L.); (S.P.)
| | - Sofía Perisset
- Instituto de Investigaciones en Medicina Traslacional (IIMT), Facultad de Ciencias Biomedicas, Universidad Austral-CONICET, Av. J.D. Perón 1500, 1629 Pilar, Buenos Aires, Argentina; (M.C.P.); (V.L.); (S.P.)
| | - Juan Eduardo Gallo
- Instituto de Investigaciones en Medicina Traslacional (IIMT), Facultad de Ciencias Biomedicas, Universidad Austral-CONICET, Av. J.D. Perón 1500, 1629 Pilar, Buenos Aires, Argentina; (M.C.P.); (V.L.); (S.P.)
- Departamento de Oftalmologia, Hospital Universitario Austral, Av. Juan Perón 1500, 1629 Pilar, Buenos Aires, Argentina
- Correspondence: ; Tel.: +54-91164038725
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Jin J, Wang H, Hua X, Chen D, Huang C, Chen Z. An outline for the pharmacological effect of icariin in the nervous system. Eur J Pharmacol 2018; 842:20-32. [PMID: 30342950 DOI: 10.1016/j.ejphar.2018.10.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 09/13/2018] [Accepted: 10/09/2018] [Indexed: 12/13/2022]
Abstract
Icariin is a major active component of the traditional herb Epimedium, also known as Horny Goat Weed. It has been extensively studied throughout the past several years and is known to exert anti-oxidative, anti-neuroinflammatory, and anti-apoptotic effects. It is now being considered as a potential therapeutic agent for a wide variety of disorders, ranging from neoplasm to cardiovascular disease. More recent studies have shown that icariin exhibits potential preventive and/or therapeutic effects in the nervous system. For example, icariin can prevent the production of amyloid β (1-42) and inhibit the expression of amyloid precursor protein (APP) and β-site APP cleaving enzyme 1 (BACE-1) in animal models of Alzheimer's disease (AD). Icariin has been shown to mitigate pro-inflammatory responses of microglia in culture and in animal models of cerebral ischemia, depression, Parkinson's disease (PD), and multiple sclerosis (MS). Icariin also prevents the neurotoxicity induced by hydrogen peroxide (H2O2), endoplasmic reticulum (ER) stress, ibotenic acid, and homocysteine. In addition, icariin is implicated in facilitating learning and memory in both normal aging animals and disease models. To date, we still have no consolidated source of knowledge about the pharmacological effects of icariin in the nervous system, though its roles in other tissues have been reviewed in recent years. Here, we summarize the pharmacological development of icariin as well as its possible mechanisms in prevention and/or therapy of disorders afflicting the nervous system in hope of expanding the knowledge about the preventive and/or therapeutic effect of icariin in brain disorders.
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Affiliation(s)
- Jie Jin
- Invasive Technology Department, Nantong First People's Hospital, the Second Affiliated Hospital of Nantong University, #6 North Road Hai'er Xiang, Nantong, Jiangsu 226001, China
| | - Hui Wang
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China; Department of Neuroscience & Cell Biology, Rutgers-Robert Wood Johnson Medical School, 675 Hoes lane, Piscataway, 08854 New Jersey, United States
| | - Xiaoying Hua
- Department of Pharmacology, Wuxi Ninth People's Hospital, #999 Liangxi Road, Wu xi, Jiangsu 226001, China
| | - Dongjian Chen
- Invasive Technology Department, Nantong First People's Hospital, the Second Affiliated Hospital of Nantong University, #6 North Road Hai'er Xiang, Nantong, Jiangsu 226001, China
| | - Chao Huang
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Zhuo Chen
- Invasive Technology Department, Nantong First People's Hospital, the Second Affiliated Hospital of Nantong University, #6 North Road Hai'er Xiang, Nantong, Jiangsu 226001, China.
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Trauelsen M, Rexen Ulven E, Hjorth SA, Brvar M, Monaco C, Frimurer TM, Schwartz TW. Receptor structure-based discovery of non-metabolite agonists for the succinate receptor GPR91. Mol Metab 2017; 6:1585-1596. [PMID: 29157600 PMCID: PMC5699910 DOI: 10.1016/j.molmet.2017.09.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 09/14/2017] [Accepted: 09/25/2017] [Indexed: 01/08/2023] Open
Abstract
Objective Besides functioning as an intracellular metabolite, succinate acts as a stress-induced extracellular signal through activation of GPR91 (SUCNR1) for which we lack suitable pharmacological tools. Methods and results Here we first determined that the cis conformation of the succinate backbone is preferred and that certain backbone modifications are allowed for GPR91 activation. Through receptor modeling over the X-ray structure of the closely related P2Y1 receptor, we discovered that the binding pocket is partly occupied by a segment of an extracellular loop and that succinate therefore binds in a very different mode than generally believed. Importantly, an empty side-pocket is identified next to the succinate binding site. All this information formed the basis for a substructure-based search query, which, combined with molecular docking, was used in virtual screening of the ZINC database to pick two serial mini-libraries of a total of only 245 compounds from which sub-micromolar, selective GPR91 agonists of unique structures were identified. The best compounds were backbone-modified succinate analogs in which an amide-linked hydrophobic moiety docked into the side-pocket next to succinate as shown by both loss- and gain-of-function mutagenesis. These compounds displayed GPR91-dependent activity in altering cytokine expression in human M2 macrophages similar to succinate, and importantly were devoid of any effect on the major intracellular target, succinate dehydrogenase. Conclusions These novel, synthetic non-metabolite GPR91 agonists will be valuable both as pharmacological tools to delineate the GPR91-mediated functions of succinate and as leads for the development of GPR91-targeted drugs to potentially treat low grade metabolic inflammation and diabetic complications such as retinopathy and nephropathy. The GPR91 binding site for succinate is identified with an adjacent empty pocket. The binding pocket structure is used to identify novel synthetic GPR91 agonists. The non-metabolite GPR91 ligands can be used as pharmacological tools and drug leads. Novel compounds demonstrate GPR91 control of cytokine expression in M2 macrophages.
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Affiliation(s)
- Mette Trauelsen
- NNF Center for Basic Metabolic Research, Section for Metabolic Receptology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark
| | - Elisabeth Rexen Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Siv A Hjorth
- Laboratory for Molecular Pharmacology, Department of Biomedical Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark
| | - Matjaz Brvar
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Claudia Monaco
- Kennedy Institute of Rheumatology, University of Oxford, Roosevelt Drive, Headington, OX3 7FY Oxford, UK
| | - Thomas M Frimurer
- NNF Center for Basic Metabolic Research, Section for Metabolic Receptology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark.
| | - Thue W Schwartz
- NNF Center for Basic Metabolic Research, Section for Metabolic Receptology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark; Laboratory for Molecular Pharmacology, Department of Biomedical Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark.
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Abstract
This overview introduces contributions to a special issue on causes of vision loss from diabetes mellitus, focusing on the retina and also the cornea. Diabetic retinopathy is the most common and leading cause of vision loss among people with diabetes. Research to detect early symptoms, understand mechanisms leading to diabetic eye disease, and the development of treatments is a highly active research area, with currently about 2000 scientific publication per year. We provide a series of 27 comprehensive reviews and research articles from leading experts in the field.
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Affiliation(s)
- M Elizabeth Hartnett
- Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Sciences, Salt Lake City, UT 84132, United States.
| | - Wolfgang Baehr
- Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Sciences, Salt Lake City, UT 84132, United States
| | - Yun Z Le
- Section of Endocrinology and Diabetes, Departments of Medicine, Cell Biology and Ophthalmology and Harold Hamm Diabetes Center, University of Oklahoma, Oklahoma City, OK 73104-5020, United States
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