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Roth-Walter F, Berni Canani R, O'Mahony L, Peroni D, Sokolowska M, Vassilopoulou E, Venter C. Nutrition in chronic inflammatory conditions: Bypassing the mucosal block for micronutrients. Allergy 2024; 79:353-383. [PMID: 38084827 DOI: 10.1111/all.15972] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/14/2023] [Accepted: 11/27/2023] [Indexed: 02/01/2024]
Abstract
Nutritional Immunity is one of the most ancient innate immune responses, during which the body can restrict nutrients availability to pathogens and restricts their uptake by the gut mucosa (mucosal block). Though this can be a beneficial strategy during infection, it also is associated with non-communicable diseases-where the pathogen is missing; leading to increased morbidity and mortality as micronutritional uptake and distribution in the body is hindered. Here, we discuss the acute immune response in respect to nutrients, the opposing nutritional demands of regulatory and inflammatory cells and particularly focus on some nutrients linked with inflammation such as iron, vitamins A, Bs, C, and other antioxidants. We propose that while the absorption of certain micronutrients is hindered during inflammation, the dietary lymph path remains available. As such, several clinical trials investigated the role of the lymphatic system during protein absorption, following a ketogenic diet and an increased intake of antioxidants, vitamins, and minerals, in reducing inflammation and ameliorating disease.
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Affiliation(s)
- Franziska Roth-Walter
- Comparative Medicine, The Interuniversity Messerli Research Institute of the University of Veterinary Medicine Vienna, Medical University Vienna and University Vienna, Vienna, Austria
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Roberto Berni Canani
- Department of Translational Medical Science and ImmunoNutritionLab at CEINGE-Advanced Biotechnologies, University of Naples "Federico II", Naples, Italy
| | - Liam O'Mahony
- Department of Medicine, School of Microbiology, APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Diego Peroni
- Section of Paediatrics, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Milena Sokolowska
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zürich, Davos, Switzerland
- Christine Kühne - Center for Allergy Research and Education (CK-CARE), Davos, Switzerland
| | - Emilia Vassilopoulou
- Pediatric Area, Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Milan, Italy
- Department of Nutritional Sciences and Dietetics, International Hellenic University, Thessaloniki, Greece
| | - Carina Venter
- Children's Hospital Colorado, University of Colorado, Aurora, Colorado, USA
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2
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Kim N, Priefer R. Retinol binding protein 4 antagonists and protein synthesis inhibitors: Potential for therapeutic development. Eur J Med Chem 2021; 226:113856. [PMID: 34547506 DOI: 10.1016/j.ejmech.2021.113856] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/07/2021] [Accepted: 09/13/2021] [Indexed: 12/12/2022]
Abstract
Retinol-binding protein 4 (RBP4) is a serum protein that transports Vitamin A. RBP4 is correlated with numerous diseases and metabolic syndromes, including insulin resistance in type 2 diabetes, cardiovascular diseases, obesity, and macular degeneration. Recently, RBP4 antagonists and protein synthesis inhibitors are under development to regulate the effect of RBP4. Several RBP4 antagonists, especially BPN-14136, have demonstrated promising safety profiles and potential therapeutic benefits in animal studies. Two RBP4 antagonists, specifically tinlarebant (Belite Bio) and STG-001 (Stargazer) are currently undergoing clinical trials. Some antidiabetic drugs and nutraceuticals have been reported to reduce RBP4 expression, but more clinical data is needed to evaluate their therapeutical benefits. As regulating RBP4 levels or its activities would benefit a wide range of patients, further research is highly recommended to develop clinically useful RBP4 antagonists or protein synthesis inhibitors.
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Affiliation(s)
- Noheul Kim
- Massachusetts College of Pharmacy and Health Sciences University, Boston, MA, USA
| | - Ronny Priefer
- Massachusetts College of Pharmacy and Health Sciences University, Boston, MA, USA.
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3
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Lioncino M, Monda E, Palmiero G, Caiazza M, Vetrano E, Rubino M, Esposito A, Salerno G, Dongiglio F, D'Onofrio B, Verrillo F, Cerciello G, Manganelli F, Pacileo G, Bossone E, Golino P, Calabrò P, Limongelli G. Cardiovascular Involvement in Transthyretin Cardiac Amyloidosis. Heart Fail Clin 2021; 18:73-87. [PMID: 34776085 DOI: 10.1016/j.hfc.2021.07.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Transthyretin cardiac amyloidosis (ATTR-CA) is a systemic disorder resulting from the extracellular deposition of amyloid fibrils of misfolded transthyretin protein in the heart. ATTR-CA is a life-threatening disease, which can be caused by progressive deposition of wild type transthyretin (wtATTR) or by aggregation of an inherited mutated variant of transthyretin (mATTR). mATTR Is a rare condition transmitted in an autosomal dominant manner with incomplete penetrance, causing heterogenous phenotypes which can range from predominant neuropathic involvement, predominant cardiomyopathy, or mixed. Diagnosis of ATTR-CA is complex and requires integration of different imaging tools (echocardiography, bone scintigraphy, magnetic resonance) with genetics, clinical signs, laboratory tests, and histology. In recent years, new therapeutic agents have shown good efficacy and impact on survival and quality of life in this subset of patients, nevertheless patients affected by ATTR-CA may still carry an unfavorable prognosis, thus highlighting the need for new therapies. This review aims to assess cardiovascular involvement, diagnosis, and management of patients affected by ATTR-CA.
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Affiliation(s)
- Michele Lioncino
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Emanuele Monda
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Giuseppe Palmiero
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Martina Caiazza
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Erica Vetrano
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy; Internal Medicine Unit, Department of Translational Sciences, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Marta Rubino
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Augusto Esposito
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Gemma Salerno
- Vanvitelli Cardiology Unit, Monaldi Hospital, Naples 80131, Italy
| | - Francesca Dongiglio
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Barbara D'Onofrio
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Federica Verrillo
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Giuseppe Cerciello
- Haematology Unit, Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy
| | - Fiore Manganelli
- Department of Neuroscience, Reproductive Sciences and Odontostomatology, University of Naples 'Federico II', Via Pansini, 5, Naples 81025, Italy
| | - Giuseppe Pacileo
- Heart Failure and Cardiac Rehabilitation Unit, Department of Cardiology, AORN dei Colli, Monaldi Hospital, Naples, Italy
| | - Eduardo Bossone
- Division of Cardiology, "Antonio Cardarelli" Hospital, Naples 80131, Italy
| | - Paolo Golino
- Vanvitelli Cardiology Unit, Monaldi Hospital, Naples 80131, Italy; Department of Translational Sciences, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Paolo Calabrò
- Department of Translational Sciences, University of Campania "Luigi Vanvitelli", Naples, Italy; Division of Cardiology, A.O.R.N. "Sant'Anna & San Sebastiano", Caserta I-81100, Italy
| | - Giuseppe Limongelli
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", AORN dei Colli, Monaldi Hospital, Naples, Italy; Institute of Cardiovascular Sciences, University College of London and St. Bartholomew's Hospital, London WC1E 6DD, UK.
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Widjaja-Adhi MAK, Golczak M. The molecular aspects of absorption and metabolism of carotenoids and retinoids in vertebrates. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158571. [PMID: 31770587 PMCID: PMC7244374 DOI: 10.1016/j.bbalip.2019.158571] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/04/2019] [Accepted: 11/07/2019] [Indexed: 02/08/2023]
Abstract
Vitamin A is an essential nutrient necessary for numerous basic physiological functions, including reproduction and development, immune cell differentiation and communication, as well as the perception of light. To evade the dire consequences of vitamin A deficiency, vertebrates have evolved specialized metabolic pathways that enable the absorption, transport, and storage of vitamin A acquired from dietary sources as preformed retinoids or provitamin A carotenoids. This evolutionary advantage requires a complex interplay between numerous specialized retinoid-transport proteins, receptors, and enzymes. Recent advances in molecular and structural biology resulted in a rapid expansion of our understanding of these processes at the molecular level. This progress opened new avenues for the therapeutic manipulation of retinoid homeostasis. In this review, we summarize current research related to the biochemistry of carotenoid and retinoid-processing proteins with special emphasis on the structural aspects of their physiological actions. This article is part of a Special Issue entitled Carotenoids recent advances in cell and molecular biology edited by Johannes von Lintig and Loredana Quadro.
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Affiliation(s)
- Made Airanthi K Widjaja-Adhi
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States of America
| | - Marcin Golczak
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States of America; Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, OH, United States of America.
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Cioffi CL, Muthuraman P, Raja A, Varadi A, Racz B, Petrukhin K. Discovery of Bispecific Antagonists of Retinol Binding Protein 4 That Stabilize Transthyretin Tetramers: Scaffolding Hopping, Optimization, and Preclinical Pharmacological Evaluation as a Potential Therapy for Two Common Age-Related Comorbidities. J Med Chem 2020; 63:11054-11084. [DOI: 10.1021/acs.jmedchem.0c00996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Christopher L. Cioffi
- Departments of Basic and Clinical Sciences and Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Avenue, Albany, New York 12208, United States
| | - Parthasarathy Muthuraman
- Departments of Basic and Clinical Sciences and Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Avenue, Albany, New York 12208, United States
| | - Arun Raja
- Departments of Basic and Clinical Sciences and Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Avenue, Albany, New York 12208, United States
| | - Andras Varadi
- Department of Ophthalmology, Columbia University Medical Center, New York, New York 10032, United States
| | - Boglarka Racz
- Department of Ophthalmology, Columbia University Medical Center, New York, New York 10032, United States
| | - Konstantin Petrukhin
- Department of Ophthalmology, Columbia University Medical Center, New York, New York 10032, United States
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6
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Racz B, Varadi A, Pearson PG, Petrukhin K. Comparative pharmacokinetics and pharmacodynamics of the advanced Retinol-Binding Protein 4 antagonist in dog and cynomolgus monkey. PLoS One 2020; 15:e0228291. [PMID: 31978148 PMCID: PMC6980506 DOI: 10.1371/journal.pone.0228291] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 01/10/2020] [Indexed: 12/23/2022] Open
Abstract
Accumulation of lipofuscin bisretinoids in the retina contributes to pathogenesis of macular degeneration. Retinol-Binding Protein 4 (RBP4) antagonists reduce serum retinol concentrations thus partially reducing retinol delivery to the retina which decreases bisretinoid synthesis. BPN-14136 is a novel RBP4 antagonist with good in vitro potency and selectivity and optimal rodent pharmacokinetic (PK) and pharmacodynamic (PD) characteristics. To select a non-rodent species for regulatory toxicology studies, we conducted PK and PD evaluation of BPN-14136 in dogs and non-human primates (NHP). PK properties were determined following oral and intravenous administration of BPN-14136 in beagle dogs and cynomolgus monkeys. Dynamics of plasma RBP4 reduction in response to compound administration was used as a PD marker. BPN-14136 exhibited favorable PK profile in both species. Dose-normalized exposure was significantly higher in NHP than in dog. Baseline concentrations of RBP4 were considerably lower in dog than in NHP, reflecting the atypical reliance of canids on non-RBP4 mechanisms of retinoid trafficking. Oral administration of BPN-14136 to NHP induced a strong 99% serum RBP4 reduction. Dynamics of RBP4 lowering in both species correlated with compound exposure. Despite adequate PK and PD characteristics of BPN-14136 in dog, reliance of canids on non-RBP4 mechanisms of retinoid trafficking precludes evaluation of on-target toxicities for RBP4 antagonists in this species. Strong RBP4 lowering combined with good PK attributes and high BPN-14136 exposure achieved in NHP, along with the biology of retinoid trafficking that is similar to that of humans, support the choice of NHP as a non-rodent safety species.
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Affiliation(s)
- Boglarka Racz
- Department of Ophthalmology, Columbia University, New York, New York, Unites States of America
| | - Andras Varadi
- Department of Ophthalmology, Columbia University, New York, New York, Unites States of America
| | - Paul G. Pearson
- Pearson Pharma Partners, Westlake Village, California, United States of America
| | - Konstantin Petrukhin
- Department of Ophthalmology, Columbia University, New York, New York, Unites States of America
- * E-mail:
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7
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Poodproh R, Kaewmeechai S, Leelawatwattana L, Prapunpoj P. Increasing the length and hydrophobicity of the C-terminal sequence of transthyretin strengthens its binding affinity to retinol binding protein. FEBS Open Bio 2017; 7:1891-1898. [PMID: 29226076 PMCID: PMC5715260 DOI: 10.1002/2211-5463.12329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/03/2017] [Accepted: 09/18/2017] [Indexed: 12/26/2022] Open
Abstract
Transthyretin (TTR) is a transporter for thyroid hormone (TH) and retinol, the latter via binding with retinol binding protein (RBP). Both the N‐terminal and C‐terminal regions of the TTR subunit are located in close proximity to the central binding channel for ligands. During the evolution of vertebrates, these regions changed in length and hydropathy. The changes in the N‐terminal sequence were demonstrated to affect the binding affinities for THs and RBP. Here, the effects of changes in the C‐terminal sequence were determined. Three chimeric TTRs, namely pigC/huTTR (human TTR with the C‐terminal sequence changed to that of Sus scrofa TTR), xenoN/pigC/huTTR (human TTR with the N‐terminal and C‐terminal sequences changed to those of Xenopus laevis and S. scrofa, respectively), and pigC/crocTTR (Crocodylus porosus TTR with the C‐terminal sequence changed to that of S. scrofa TTR), were constructed and their binding affinities for human RBP were determined at low TTR/RBP molar ratio using chemiluminescence immunoblotting. The binding dissociation constant (Kd) values of pigC/huTTR, xenoN/pigC/huTTR and pigC/crocTTR were 3.20 ± 0.35, 1.53 ± 0.38 and 0.31 ± 0.04 μm, respectively, and the Kd values of human and C. porosus TTR were 4.92 ± 0.68 and 1.42 ± 0.45 μm, respectively. These results demonstrate chimeric TTRs bound RBP with a higher strength than wild‐type TTRs, and the changes in the C‐terminal sequence of TTR had a positive effect on its binding affinity for RBP. In addition, changes to the N‐terminal and C‐terminal sequences showed comparable effects on the binding affinity.
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Affiliation(s)
- Rattawan Poodproh
- Department of Biochemistry Faculty of Science Prince of Songkla University Hat Yai Thailand
| | - Supavadee Kaewmeechai
- Department of Biochemistry Faculty of Science Prince of Songkla University Hat Yai Thailand
| | - Ladda Leelawatwattana
- Department of Biochemistry Faculty of Science Prince of Songkla University Hat Yai Thailand
| | - Porntip Prapunpoj
- Department of Biochemistry Faculty of Science Prince of Songkla University Hat Yai Thailand
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8
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Buxbaum JN, Johansson J. Transthyretin and BRICHOS: The Paradox of Amyloidogenic Proteins with Anti-Amyloidogenic Activity for Aβ in the Central Nervous System. Front Neurosci 2017; 11:119. [PMID: 28360830 PMCID: PMC5350149 DOI: 10.3389/fnins.2017.00119] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 02/27/2017] [Indexed: 01/19/2023] Open
Abstract
Amyloid fibrils are physiologically insoluble biophysically specific β-sheet rich structures formed by the aggregation of misfolded proteins. In vivo tissue amyloid formation is responsible for more than 30 different disease states in humans and other mammals. One of these, Alzheimer's disease (AD), is the most common form of human dementia for which there is currently no definitive treatment. Amyloid fibril formation by the amyloid β-peptide (Aβ) is considered to be an underlying cause of AD, and strategies designed to reduce Aβ production and/or its toxic effects are being extensively investigated in both laboratory and clinical settings. Transthyretin (TTR) and proteins containing a BRICHOS domain are etiologically associated with specific amyloid diseases in the CNS and other organs. Nonetheless, it has been observed that TTR and BRICHOS structures are efficient inhibitors of Aβ fibril formation and toxicity in vitro and in vivo, raising the possibility that some amyloidogenic proteins, or their precursors, possess properties that may be harnessed for combating AD and other amyloidoses. Herein, we review properties of TTR and the BRICHOS domain and discuss how their abilities to interfere with amyloid formation may be employed in the development of novel treatments for AD.
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Affiliation(s)
- Joel N Buxbaum
- Department of Molecular and Experimental Medicine, The Scripps Research InstituteLa Jolla, CA, USA; Scintillon InstituteSan Diego, CA, USA
| | - Jan Johansson
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences, and Society (NVS), Center for Alzheimer Research, Karolinska Institutet Huddinge, Sweden
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Coelho T, Merlini G, Bulawa CE, Fleming JA, Judge DP, Kelly JW, Maurer MS, Planté-Bordeneuve V, Labaudinière R, Mundayat R, Riley S, Lombardo I, Huertas P. Mechanism of Action and Clinical Application of Tafamidis in Hereditary Transthyretin Amyloidosis. Neurol Ther 2016; 5:1-25. [PMID: 26894299 PMCID: PMC4919130 DOI: 10.1007/s40120-016-0040-x] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Indexed: 11/24/2022] Open
Abstract
Transthyretin (TTR) transports the retinol-binding protein-vitamin A complex and is a minor transporter of thyroxine in blood. Its tetrameric structure undergoes rate-limiting dissociation and monomer misfolding, enabling TTR to aggregate or to become amyloidogenic. Mutations in the TTR gene generally destabilize the tetramer and/or accelerate tetramer dissociation, promoting amyloidogenesis. TTR-related amyloidoses are rare, fatal, protein-misfolding disorders, characterized by formation of soluble aggregates of variable structure and tissue deposition of amyloid. The TTR amyloidoses present with a spectrum of manifestations, encompassing progressive neuropathy and/or cardiomyopathy. Until recently, the only accepted treatment to halt progression of hereditary TTR amyloidosis was liver transplantation, which replaces the hepatic source of mutant TTR with the less amyloidogenic wild-type TTR. Tafamidis meglumine is a rationally designed, non-NSAID benzoxazole derivative that binds with high affinity and selectivity to TTR and kinetically stabilizes the tetramer, slowing monomer formation, misfolding, and amyloidogenesis. Tafamidis is the first pharmacotherapy approved to slow the progression of peripheral neurologic impairment in TTR familial amyloid polyneuropathy. Here we describe the mechanism of action of tafamidis and review the clinical data, demonstrating that tafamidis treatment slows neurologic deterioration and preserves nutritional status, as well as quality of life in patients with early-stage Val30Met amyloidosis.
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Affiliation(s)
- Teresa Coelho
- Hospital de Santo António, Centro Hospitalar do Porto, Porto, Portugal.
| | - Giampaolo Merlini
- Foundation IRCCS Policlinico San Matteo, University of Pavia, Pavia, Italy
| | | | | | - Daniel P Judge
- Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Mathew S Maurer
- Columbia University College of Physicians and Surgeons, New York, NY, USA
| | | | | | | | | | | | - Pedro Huertas
- Massachusetts General and McLean Hospitals, Harvard Medical School, Boston, MA, USA
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Cioffi CL, Racz B, Freeman EE, Conlon MP, Chen P, Stafford DG, Schwarz DMC, Zhu L, Kitchen DB, Barnes KD, Dobri N, Michelotti E, Cywin CL, Martin WH, Pearson PG, Johnson G, Petrukhin K. Bicyclic [3.3.0]-Octahydrocyclopenta[c]pyrrolo Antagonists of Retinol Binding Protein 4: Potential Treatment of Atrophic Age-Related Macular Degeneration and Stargardt Disease. J Med Chem 2015; 58:5863-88. [PMID: 26181715 DOI: 10.1021/acs.jmedchem.5b00423] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Antagonists of retinol-binding protein 4 (RBP4) impede ocular uptake of serum all-trans retinol (1) and have been shown to reduce cytotoxic bisretinoid formation in the retinal pigment epithelium (RPE), which is associated with the pathogenesis of both dry age-related macular degeneration (AMD) and Stargardt disease. Thus, these agents show promise as a potential pharmacotherapy by which to stem further neurodegeneration and concomitant vision loss associated with geographic atrophy of the macula. We previously disclosed the discovery of a novel series of nonretinoid RBP4 antagonists, represented by bicyclic [3.3.0]-octahydrocyclopenta[c]pyrrolo analogue 4. We describe herein the utilization of a pyrimidine-4-carboxylic acid fragment as a suitable isostere for the anthranilic acid appendage of 4, which led to the discovery of standout antagonist 33. Analogue 33 possesses exquisite in vitro RBP4 binding affinity and favorable drug-like characteristics and was found to reduce circulating plasma RBP4 levels in vivo in a robust manner (>90%).
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Affiliation(s)
| | - Boglarka Racz
- §Department of Ophthalmology, Columbia University Medical Center, New York, New York 10032, United States
| | | | | | | | | | | | | | | | | | - Nicoleta Dobri
- §Department of Ophthalmology, Columbia University Medical Center, New York, New York 10032, United States
| | - Enrique Michelotti
- #National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Charles L Cywin
- ○National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - William H Martin
- ⊥WHM Consulting LLC, 111 Sterling City Road, Lyme, Connecticut 06371, United States
| | - Paul G Pearson
- ∥iCuraVision LLC, 31194 La Baya Drive, Suite 101, Westlake Village, California 91362, United States
| | - Graham Johnson
- ∥iCuraVision LLC, 31194 La Baya Drive, Suite 101, Westlake Village, California 91362, United States
| | - Konstantin Petrukhin
- §Department of Ophthalmology, Columbia University Medical Center, New York, New York 10032, United States
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11
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Ferreira N, Pereira-Henriques A, Almeida MR. Transthyretin chemical chaperoning by flavonoids: Structure-activity insights towards the design of potent amyloidosis inhibitors. Biochem Biophys Rep 2015; 3:123-133. [PMID: 29124175 PMCID: PMC5668852 DOI: 10.1016/j.bbrep.2015.07.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 07/29/2015] [Accepted: 07/31/2015] [Indexed: 11/24/2022] Open
Abstract
Background Many polyphenols have been proposed as broad-spectrum inhibitors of amyloid formation. To investigate structure–activity relationships relevant for the interaction of flavonoids with transthyretin (TTR), the protein associated with familial amyloid polyneuropathy (FAP), we compared the effects of major tea catechins and their larger polymers theaflavins, side-by-side, on TTR amyloid formation process. Methods Interaction of flavonoids with TTR and effect on TTR stability were assessed through binding assays and isoelectric focusing in polyacrylamide gel. TTR aggregation was studied, in vitro, by dynamic light scattering (DLS), transmission electron microscopy (TEM) and in cell culture, through cytotoxicity assays. Results Tested flavonoids bound to TTR and stabilized the TTR tetramer, with different potencies. The flavonoids also inhibited in vitro formation of TTR small oligomeric species and in cell culture inhibited pathways involving caspase-3 activation and ER stress that are induced by TTR oligomers. In all assays performed the galloyl esters presented higher potency to inhibit aggregation than the non-gallated flavonoids tested. Conclusions Our results highlight the presence of gallate ester moiety as key structural feature of flavonoids in chemical chaperoning of TTR aggregation. Upon binding to the native tetramer, gallated flavonoids redirect the TTR amyloidogenic pathway into unstructured nontoxic aggregation assemblies more efficiently than their non-gallated forms. General significance Our findings suggest that galloyl moieties greatly enhance flavonoid anti-amyloid chaperone activity and this should be taken into consideration in therapeutic candidate drug discovery. Flavonoids are broad-spectrum inhibitors of TTR amyloid formation. The galloyl moiety is essential for chemical chaperoning of TTR by flavonoids. The galloyl moiety may be important for the design of new therapeutic agents for FAP.
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Affiliation(s)
- Nelson Ferreira
- IBMC-Instituto de Biologia Molecular e Celular, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.,I3S-Instituto de Inovação e Investigação em Saúde, Universidade do Porto, Porto, Portugal
| | - Alda Pereira-Henriques
- IBMC-Instituto de Biologia Molecular e Celular, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.,I3S-Instituto de Inovação e Investigação em Saúde, Universidade do Porto, Porto, Portugal
| | - Maria Rosário Almeida
- IBMC-Instituto de Biologia Molecular e Celular, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.,I3S-Instituto de Inovação e Investigação em Saúde, Universidade do Porto, Porto, Portugal.,ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
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Alshehri B, D'Souza DG, Lee JY, Petratos S, Richardson SJ. The diversity of mechanisms influenced by transthyretin in neurobiology: development, disease and endocrine disruption. J Neuroendocrinol 2015; 27:303-23. [PMID: 25737004 DOI: 10.1111/jne.12271] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 12/12/2022]
Abstract
Transthyretin (TTR) is a protein that binds and distributes thyroid hormones (THs). TTR synthesised in the liver is secreted into the bloodstream and distributes THs around the body, whereas TTR synthesised in the choroid plexus is involved in movement of thyroxine from the blood into the cerebrospinal fluid and the distribution of THs in the brain. This is important because an adequate amount of TH is required for normal development of the brain. Nevertheless, there has been heated debate on the role of TTR synthesised by the choroid plexus during the past 20 years. We present both sides of the debate and how they can be reconciled by the discovery of TH transporters. New roles for TTR have been suggested, including the promotion of neuroregeneration, protection against neurodegeneration, and involvement in schizophrenia, behaviour, memory and learning. Recently, TTR synthesis was revealed in neurones and peripheral Schwann cells. Thus, the synthesis of TTR in the central nervous system (CNS) is more extensive than previously considered and bolsters the hypothesis that TTR may play wide roles in neurobiological function. Given the high conservation of TTR structure, function and tissue specificity and timing of gene expression, this implies that TTR has a fundamental role, during development and in the adult, across vertebrates. An alarming number of 'unnatural' chemicals can bind to TTR, thus potentially interfering with its functions in the brain. One role of TTR is delivery of THs throughout the CNS. Reduced TH availability during brain development results in a reduced IQ. The combination of the newly discovered sites of TTR synthesis in the CNS, the increasing number of neurological diseases being associated with TTR, the newly discovered functions of TTR and the awareness of the chemicals that can interfere with TTR biology render this a timely review on TTR in neurobiology.
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Affiliation(s)
- B Alshehri
- School of Medical Sciences, RMIT University, Bundoora, VIC, Australia
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Cioffi CL, Dobri N, Freeman EE, Conlon MP, Chen P, Stafford DG, Schwarz DMC, Golden KC, Zhu L, Kitchen DB, Barnes KD, Racz B, Qin Q, Michelotti E, Cywin CL, Martin WH, Pearson PG, Johnson G, Petrukhin K. Design, synthesis, and evaluation of nonretinoid retinol binding protein 4 antagonists for the potential treatment of atrophic age-related macular degeneration and Stargardt disease. J Med Chem 2014; 57:7731-57. [PMID: 25210858 PMCID: PMC4174998 DOI: 10.1021/jm5010013] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
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Accumulation of lipofuscin in the
retina is associated with pathogenesis
of atrophic age-related macular degeneration and Stargardt disease.
Lipofuscin bisretinoids (exemplified by N-retinylidene-N-retinylethanolamine) seem to mediate lipofuscin toxicity.
Synthesis of lipofuscin bisretinoids depends on the influx of retinol
from serum to the retina. Compounds antagonizing the retinol-dependent
interaction of retinol-binding protein 4 (RBP4) with transthyretin
in the serum would reduce serum RBP4 and retinol and inhibit bisretinoid
formation. We recently showed that A1120 (3), a potent
carboxylic acid based RBP4 antagonist, can significantly reduce lipofuscin
bisretinoid formation in the retinas of Abca4–/– mice. As part of the NIH
Blueprint Neurotherapeutics Network project we undertook the in vitro exploration to identify novel conformationally flexible and constrained
RBP4 antagonists with improved potency and metabolic stability. We
also demonstrate that upon acute and chronic dosing in rats, 43, a potent cyclopentyl fused pyrrolidine antagonist, reduced
circulating plasma RBP4 protein levels by approximately 60%.
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Affiliation(s)
- Christopher L Cioffi
- Department of Medicinal Chemistry, Albany Molecular Research, Inc. , East Campus, C-Wing, Rensselaer, New York 12144, United States
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14
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Popov IA, Starodubtseva NL, Indeikina MI, Kostyukevich YI, Kononikhin AS, Nikolaeva MI, Kukaev EN, Kozin SA, Makarov AA, Nikolaev EN. Mass spectrometric identification of posttranslational modifications in transthyretin from human blood. Mol Biol 2013. [DOI: 10.1134/s0026893313060125] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Petrukhin K. Pharmacological inhibition of lipofuscin accumulation in the retina as a therapeutic strategy for dry AMD treatment. ACTA ACUST UNITED AC 2013; 10:e11-e20. [PMID: 25152755 DOI: 10.1016/j.ddstr.2013.05.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in the western world. There is no FDA-approved treatment for the most prevalent dry (atrophic) form of AMD. Photoreceptor degeneration in dry AMD is triggered by abnormalities in the retinal pigment epithelium (RPE). It has been suggested that excessive accumulation of fluorescent lipofuscin pigment in the RPE represents an important pathogenic factor in etiology and progression of dry AMD. Cytotoxic lipofuscin bisretinoids, such as A2E, are formed in the retina in a non-enzymatic way from visual cycle retinoids. Inhibition of toxic bisretinoid production in the retina seems to be a sound treatment strategy for dry AMD. In this review we discuss the following classes of pharmacological treatments inhibiting lipofuscin bisretinoid formation in the retina: direct inhibitors of key visual cycle enzymes, RBP4 antagonists, primary amine-containing aldehyde traps, and deuterated analogs of vitamin A.
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Kraft R, Herndon DN, Kulp GA, Mecott GA, Trentzsch H, Jeschke MG. Retinol binding protein: marker for insulin resistance and inflammation postburn? JPEN J Parenter Enteral Nutr 2012; 35:695-703. [PMID: 22042048 DOI: 10.1177/0148607111413901] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Burn injury leads to vast changes in both metabolic and inflammatory responses and is associated with increased morbidity and mortality. Insulin resistance (IR) and hyperglycemia are major components of the hypermetabolic response found in burn-injured patients and subsequently contribute to adverse outcomes. Studies have shown that increased systemic retinol binding protein (RBP) levels are associated with IR and hyperinflammation in diabetic and obese patients. The aim of this study was to determine RBP profiles and to test the hypothesis that elevated RBP levels are associated with both IR and the inflammatory response in burned patients. METHODS RBP was measured in 372 patients during the acute stay postburn. Patients' demographics, glucose levels, and insulin administration were recorded. Cytokines, hormones, plasma proteins, and organ markers were measured. The average of all measurements of RBP (2.1 mg/dL) was used to divide patients into high and low groups. Statistical analysis was performed by Student t test. Statistical significance was accepted at P < .05. RESULTS Fifty-one patients (high group) had elevated RBP levels during acute hospitalization and demonstrated a significant higher incidence of multiorgan failure, sepsis, and mortality (P < .05). Moreover, in the high group, a significant increase of IR, inflammatory cytokines, and catabolic and organ-specific markers were detected (P < .05). CONCLUSIONS Increased RBP levels postburn correlate with increased IR, inflammatory and catabolic responses, incidence of multiorgan failure, and mortality. RBP may be a novel biomarker to monitor these detrimental responses postburn.
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Affiliation(s)
- Robert Kraft
- Shriners Hospitals for Children, and Department of Surgery, University of Texas Medical Branch Galveston, Texas, USA
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Li X, Buxbaum JN. Transthyretin and the brain re-visited: is neuronal synthesis of transthyretin protective in Alzheimer's disease? Mol Neurodegener 2011; 6:79. [PMID: 22112803 PMCID: PMC3267701 DOI: 10.1186/1750-1326-6-79] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2011] [Accepted: 11/23/2011] [Indexed: 12/14/2022] Open
Abstract
Since the mid-1990's a trickle of publications from scattered independent laboratories have presented data suggesting that the systemic amyloid precursor transthyretin (TTR) could interact with the amyloidogenic β-amyloid (Aβ) peptide of Alzheimer's disease (AD). The notion that one amyloid precursor could actually inhibit amyloid fibril formation by another seemed quite far-fetched. Further it seemed clear that within the CNS, TTR was only produced in choroid plexus epithelial cells, not in neurons. The most enthusiastic of the authors proclaimed that TTR sequestered Aβ in vivo resulting in a lowered TTR level in the cerebrospinal fluid (CSF) of AD patients and that the relationship was salutary. More circumspect investigators merely showed in vitro interaction between the two molecules. A single in vivo study in Caenorhabditis elegans suggested that wild type human TTR could suppress the abnormalities seen when Aβ was expressed in the muscle cells of the worm. Subsequent studies in human Aβ transgenic mice, including those from our laboratory, also suggested that the interaction reduced the Aβ deposition phenotype. We have reviewed the literature analyzing the relationship including recent data examining potential mechanisms that could explain the effect. We have proposed a model which is consistent with most of the published data and current notions of AD pathogenesis and can serve as a hypothesis which can be tested.
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Affiliation(s)
- Xinyi Li
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Rd,, MEM-230, La Jolla, CA 92037, USA
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Leelawatwattana L, Praphanphoj V, Prapunpoj P. Effect of the N-terminal sequence on the binding affinity of transthyretin for human retinol-binding protein. FEBS J 2011; 278:3337-47. [PMID: 21777382 DOI: 10.1111/j.1742-4658.2011.08249.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
During vertebrate evolution, the N-terminal region of transthyretin (TTR) subunit has undergone a change in both length and hydropathy. This was previously shown to change the binding affinity for thyroid hormones (THs). However, it was not known whether this change affects other functions of TTR. In the present study, the effect of these changes on the binding of TTR to retinol-binding protein (RBP) was determined. Two wild-type TTRs from human and Crocodylus porosus, and three chimeric TTRs, including a human chimeric TTR in which its N-terminal sequence was changed to that of C. porosus TTR (croc/huTTR) and two C. porosus chimeric TTRs (hu/crocTTR in which its N-terminal sequence was changed to that of human TTR and xeno/crocTTR in which its N-terminal sequence was changed to that of Xenopus laevis TTR), were analyzed for their binding to human RBP by native-PAGE followed by immunoblotting and a chemilluminescence assay. The K(d) of human TTR was 30.41 ± 2.03 μm, and was similar to that reported for the second binding site, whereas that of crocodile TTR was 2.19 ± 0.24 μm. The binding affinities increased in croc/huTTR (K(d) = 23.57 ± 3.54 μm) and xeno/crocTTR (K(d) = 0.61 ± 0.16 μm) in which their N-termini were longer and more hydrophobic, but decreased in hu/crocTTR (K(d) = 5.03 ± 0.68 μm) in which its N-terminal region was shorter and less hydrophobic. These results suggest an influence of the N-terminal primary structure of TTR on its function as a co-carrier for retinol with RBP.
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Affiliation(s)
- Ladda Leelawatwattana
- Department of Biochemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand
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Disorder-to-order conformational transitions in protein structure and its relationship to disease. Mol Cell Biochem 2009; 330:105-20. [PMID: 19357935 DOI: 10.1007/s11010-009-0105-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 03/30/2009] [Indexed: 01/22/2023]
Abstract
Function in proteins largely depends on the acquisition of specific structures through folding at physiological time scales. Under both equilibrium and non-equilibrium states, proteins develop partially structured molecules that being intermediates in the process, usually resemble the structure of the fully folded protein. These intermediates, known as molten globules, present the faculty of adopting a large variety of conformations mainly supported by changes in their side chains. Taking into account that the mechanism to obtain a fully packed structure is considered more difficult energetically than forming partially "disordered" folding intermediates, evolution might have conferred upon an important number of proteins the capability to first partially fold and-depending on the presence of specific partner ligands-switch on disorder-to-order transitions to adopt a highly ordered well-folded state and reach the lowest energy conformation possible. Disorder in this context can represent segments of proteins or complete proteins that might exist in the native state. Moreover, because this type of disorder-to-order transition in proteins has been found to be reversible, it has been frequently associated with important signaling events in the cell. Due to the central role of this phenomenon in cell biology, protein misfolding and aberrant disorder-to-order transitions have been at present associated with an important number of diseases.
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Van Beneden K, van Grunsven LA, Geers C, Pauwels M, Desmoulière A, Verbeelen D, Geerts A, Van den Branden C. CRBP-I in the renal tubulointerstitial compartment of healthy rats and rats with renal fibrosis. Nephrol Dial Transplant 2008; 23:3464-71. [PMID: 18503097 DOI: 10.1093/ndt/gfn290] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Cellular retinol-binding protein I (CRBP-I), a member of the intracellular lipid-binding protein (iLBP) superfamily, is a specific marker of quiescent stellate cells in the healthy human liver. In the diseased fibrotic/cirrhotic liver, portal and septal myofibroblasts acquire CRBP-I expression, while activated hepatic stellate cells maintain their CRBP-I expression. Here, we investigate the distribution of CRBP-I in the renal cortex of healthy rats and rats with renal fibrosis. METHODS Kidneys of healthy and adriamycin-treated rats were studied by immunohistochemistry, using antibodies against CRBP-I, desmin, vimentin and alpha-smooth muscle actin (alpha-SMA). Double stainings were done with immunofluorescence. Western blotting was performed to semi-quantify the expression levels of vimentin, desmin, alpha-SMA and CRBP-I. RESULTS In the normal rat kidney, the convoluted proximal tubular epithelial cells express CRBP-I; no expression is found in the interstitium, nor in the glomeruli. In the adriamycin-induced fibrotic rat kidney, CRBP-I expression diminishes in the convoluted proximal tubular epithelial cells, whereas peritubular myofibroblasts in the interstitium acquire CRBP-I expression. CONCLUSIONS In the tubulointerstitial compartment of the adriamycin-induced fibrotic rat kidney, CRBP-I is expressed in a different pattern than in the healthy rat kidney. As the convoluted proximal tubular epithelial cells dedifferentiate during fibrosis, CRBP-I expression decreases. Furthermore, de novo expression of CRBP-I is found in activated myofibroblast-like cells in the interstitium of adriamycin-treated rats. CRBP-I is therefore a useful marker to identify a subpopulation of activated/ myodifferentiated fibroblasts in the rat kidney.
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Affiliation(s)
- Katrien Van Beneden
- Vrije Universiteit Brussel, Menselijke Anatomie, Laarbeeklaan 103, B-1090 Brussels, Belgium.
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Eberini I, Fantucci P, Rocco AG, Gianazza E, Galluccio L, Maggioni D, Ben ID, Galliano M, Mazzitello R, Gaiji N, Beringhelli T. Computational and experimental approaches for assessing the interactions between the model calycin β-lactoglobulin and two antibacterial fluoroquinolones. Proteins 2006; 65:555-67. [PMID: 17001652 DOI: 10.1002/prot.21109] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Norfloxacin and levofloxacin, two fluoroquinolones of different bulk, rigidity and hydrophobicity taken as model ligands, were docked to one apo and two holo crystallographic structures of bovine beta-lactoglobulin (BLG) using different computational approaches. BLG is a member of the lipocalin superfamily. Lipocalins show a typical b-barrel structure encompassing an internal cavity where small hydrophobic molecules are usually bound. Our studies allowed the identification of two putative binding sites in addition to the calyx. The rigid docking approximation resulted in strong repulsive forces when the ligands were docked into the calyx of the apo form. On the contrary, hindrance was not experienced in flexible docking protocols whether on the apo or on the holo BLG forms, due to allowance for side chain rearrangement. K(i) between 10(-7) and 10(-6) M were estimated for norfloxacin at pH 7.4, smaller than 10(-5) M for levofloxacin. Spectroscopic and electrophoretic techniques experimentally validated the occurrence of an interaction between norfloxacin and BLG. Changes in chemical shift and dynamic parameters were observed between the (19)F NMR spectra of the complex and of the ligand. A K(i) (ca 10(-7) M) comparable with the docking results was estimated through a NMR relaxation titration. Stabilization against unfolding was demonstrated by denaturant gradient gel electrophoresis on the complex versus apo BLG. NMR experimental evidence points to a very loose interaction for ofloxacin, the racemic mixture containing levofloxacin. Furthermore, we were able to calculate in silico K(i)'s comparable to the published experimental values for the complexes of palmitic and retinoic acid with BLG.
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Affiliation(s)
- Ivano Eberini
- Gruppo di Studio per la Proteomica e la Struttura delle Proteine, Dipartimento di Scienze Farmacologiche, Università degli Studi di Milano, Milano, Italia
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