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Hashmi MU, Ahmed R, Mahmoud S, Ahmed K, Bushra NM, Ahmed A, Elwadie B, Madni A, Saad AB, Abdelrahman N. Exploring Methylene Blue and Its Derivatives in Alzheimer's Treatment: A Comprehensive Review of Randomized Control Trials. Cureus 2023; 15:e46732. [PMID: 38022191 PMCID: PMC10631450 DOI: 10.7759/cureus.46732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
Methylene blue (MB) and its compounds are investigated for their potential benefits in the management of Alzheimer's disease (AD). AD is a widely seen neuropathological disorder characterized by the gradual decline of cognitive abilities, ultimately leading to the development of severe dementia. It is anticipated that there will be a significant increase in the prevalence of AD due to the aging population. Histopathologically, AD is distinguished by the presence of intracellular tangles of neurofibrillary tissues (NFTs) and extracellular amyloid plaques within the brain. MB is a thiophenazine dye with FDA approval for treating several illnesses. Its ease in crossing the blood-brain barrier and potential therapeutic use in central nervous system diseases have increased interest in its application for treating AD. The literature review includes randomized clinical trials investigating MB's potential benefits in treating AD. The findings of the studies indicate that the administration of MB has demonstrated enhancements in cognitive function, reductions in the accumulation of plaques containing beta-amyloid, improvements in memory and cognitive function in animal subjects, and possesses antioxidant properties that can mitigate oxidative stress and inflammation within the brain. This review evaluates the modern and latest research on the application of MB for treating AD.
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Affiliation(s)
| | - Ragda Ahmed
- Internal Medicine, White River Health, Batesville, USA
| | - Sulafa Mahmoud
- Internal Medicine, Michigan State University, East Lansing, USA
| | - Kholood Ahmed
- Internal Medicine, College of Human Medicine, Michigan State University, East Lansing, USA
| | - Noura M Bushra
- Internal Medicine, Michigan State University, East Lansing, USA
| | - Areeg Ahmed
- Nephrology, Harlem Hospital Center, Columbia University, New York, USA
| | - Batran Elwadie
- Internal Medicine, Michigan State University, East Lansing, USA
| | - Amna Madni
- Internal Medicine, Michigan State University, East Lansing, USA
| | - Amel B Saad
- Internal Medicine, Michigan State University, East Lansing, USA
| | - Nadir Abdelrahman
- Family Medicine, College of Human Medicine, Michigan State University, East Lansing, USA
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Isaev D, Yang KHS, Petroianu G, Lorke DE, Oz M. Methylene Blue Inhibits Cromakalim-Activated K + Currents in Follicle-Enclosed Oocytes. MEMBRANES 2023; 13:121. [PMID: 36837624 PMCID: PMC9966726 DOI: 10.3390/membranes13020121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/19/2022] [Accepted: 01/05/2023] [Indexed: 06/18/2023]
Abstract
The effects of methylene blue (MB) on cromakalim-induced K+ currents were investigated in follicle-enclosed Xenopus oocytes. In concentrations ranging from 3-300 μM, MB inhibited K+ currents (IC50: 22.4 μM) activated by cromakalim, which activates KATP channels. MB inhibited cromakalim-activated K+ currents in a noncompetitive and voltage-independent manner. The respective EC50 and slope values for cromakalim-activation of K+ currents were 194 ± 21 µM and 0.91 for controls, and 206 ± 24 µM and 0.87 in the presence of 30 μM MB. The inhibition of cromakalim-induced K+ currents by MB was not altered by pretreatment with the Ca2+ chelator BAPTA, which suggests that MB does not influence Ca2+-activated second messenger pathways. K+ currents mediated through a C-terminally deleted form of Kir6.2 (KirΔC26), which does not contain the sulfonylurea receptor, were still inhibited by MB, indicating direct interaction of MB with the channel-forming Kir6.2 subunit. The binding characteristics of the KATP ligand [3H]glibenclamide are not altered by MB in a concentration range between 1 μM-1 mM, as suggested by radioligand binding assay. The presence of a membrane permeable cGMP analogue (8-Br-cGMP, 100 µM) and a guanylate cyclase activator (BAY 58-2667, 3 µM) did not affect the inhibitory effects of MB, suggesting that MB does not inhibit cromakalim-activated K+ currents through guanylate cyclase. Collectively, these results suggest that MB directly inhibits cromakalim-activated K+ currents in follicular cells of Xenopus oocytes.
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Affiliation(s)
- Dmytro Isaev
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, 01024 Kiev, Ukraine
| | - Keun-Hang Susan Yang
- Department of Biological Sciences, Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA 92866, USA
| | - Georg Petroianu
- Department of Pharmacology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi 127788, United Arab Emirates
| | - Dietrich Ernst Lorke
- Department of Anatomy and Cellular Biology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi 127788, United Arab Emirates
| | - Murat Oz
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Kuwait University, Safat 13110, Kuwait
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Bandaru LJM, Ayyalasomayajula N, Murumulla L, Challa S. Mechanisms associated with the dysregulation of mitochondrial function due to lead exposure and possible implications on the development of Alzheimer's disease. Biometals 2022; 35:1-25. [PMID: 35048237 DOI: 10.1007/s10534-021-00360-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 12/09/2021] [Indexed: 01/17/2023]
Abstract
Lead (Pb) is a multimedia contaminant with various pathophysiological consequences, including cognitive decline and neural abnormalities. Recent findings have reported an association of Pb toxicity with Alzheimer's disease (AD). Studies have revealed that mitochondrial dysfunction is a pathological characteristic of AD. According to toxicology reports, Pb promotes mitochondrial oxidative stress by lowering complex III activity in the electron transport chain, boosting reactive oxygen species formation, and reducing the cell's antioxidant defence system. Here, we review recent advances in the role of mitochondria in Pb-induced AD pathology, as well as the mechanisms associated with the mitochondrial dysfunction, such as the depolarisation of the mitochondrial membrane potential, mitochondrial permeability transition pore opening; mitochondrial biogenesis, bioenergetics and mitochondrial dynamics alterations; and mitophagy and apoptosis. We also discuss possible therapeutic options for mitochondrial-targeted neurodegenerative disease (AD).
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Affiliation(s)
- Lakshmi Jaya Madhuri Bandaru
- Department of Cell Biology, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - Neelima Ayyalasomayajula
- Department of Cell Biology, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - Lokesh Murumulla
- Department of Cell Biology, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - Suresh Challa
- Department of Cell Biology, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India.
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Limorenko G, Lashuel HA. Revisiting the grammar of Tau aggregation and pathology formation: how new insights from brain pathology are shaping how we study and target Tauopathies. Chem Soc Rev 2021; 51:513-565. [PMID: 34889934 DOI: 10.1039/d1cs00127b] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Converging evidence continues to point towards Tau aggregation and pathology formation as central events in the pathogenesis of Alzheimer's disease and other Tauopathies. Despite significant advances in understanding the morphological and structural properties of Tau fibrils, many fundamental questions remain about what causes Tau to aggregate in the first place. The exact roles of cofactors, Tau post-translational modifications, and Tau interactome in regulating Tau aggregation, pathology formation, and toxicity remain unknown. Recent studies have put the spotlight on the wide gap between the complexity of Tau structures, aggregation, and pathology formation in the brain and the simplicity of experimental approaches used for modeling these processes in research laboratories. Embracing and deconstructing this complexity is an essential first step to understanding the role of Tau in health and disease. To help deconstruct this complexity and understand its implication for the development of effective Tau targeting diagnostics and therapies, we firstly review how our understanding of Tau aggregation and pathology formation has evolved over the past few decades. Secondly, we present an analysis of new findings and insights from recent studies illustrating the biochemical, structural, and functional heterogeneity of Tau aggregates. Thirdly, we discuss the importance of adopting new experimental approaches that embrace the complexity of Tau aggregation and pathology as an important first step towards developing mechanism- and structure-based therapies that account for the pathological and clinical heterogeneity of Alzheimer's disease and Tauopathies. We believe that this is essential to develop effective diagnostics and therapies to treat these devastating diseases.
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Affiliation(s)
- Galina Limorenko
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Federal de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Federal de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
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Shiells H, Schelter BO, Bentham P, Baddeley TC, Rubino CM, Ganesan H, Hammel J, Vuksanovic V, Staff RT, Murray AD, Bracoud L, Wischik DJ, Riedel G, Gauthier S, Jia J, Moebius HJ, Hardlund J, Kipps CM, Kook K, Storey JMD, Harrington CR, Wischik CM. Concentration-Dependent Activity of Hydromethylthionine on Clinical Decline and Brain Atrophy in a Randomized Controlled Trial in Behavioral Variant Frontotemporal Dementia. J Alzheimers Dis 2021; 75:501-519. [PMID: 32280089 PMCID: PMC7306898 DOI: 10.3233/jad-191173] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Hydromethylthionine is a potent inhibitor of pathological aggregation of tau and TDP-43 proteins. OBJECTIVE To compare hydromethylthionine treatment effects at two doses and to determine how drug exposure is related to treatment response in bvFTD. METHODS We undertook a 52-week Phase III study in 220 bvFTD patients randomized to compare hydromethylthionine at 200 mg/day and 8 mg/day (intended as a control). The principal outcomes were change on the Addenbrookes Cognitive Examination - Revised (ACE-R), the Functional Activities Questionnaire (FAQ), and whole brain volume. Secondary outcomes included Modified Clinical Global Impression of Change (Modified-CGIC). A population pharmacokinetic exposure-response analysis was undertaken in 175 of the patients with available blood samples and outcome data using a discriminatory plasma assay for the parent drug. RESULTS There were no significant differences between the two doses as randomized. There were steep concentration-response relationships for plasma levels in the range 0.3-0.6 ng/ml at the 8 mg/day dose on clinical and MRI outcomes. There were significant exposure-dependent differences at 8 mg/day for FAQ, Modified-CGIC, and whole brain atrophy comparing patients with plasma levels greater than 0.346 ng/ml with having minimal drug exposure. The exposure-response is biphasic with worse outcomes at the high concentrations produced by 200 mg/day. CONCLUSIONS Hydromethylthionine has a similar concentration-response profile for effects on clinical decline and brain atrophy at the 8 mg/day dose in bvFTD as recently reported in AD. Treatment responses in bvFTD are predicted to be maximal at doses in the range 20-60 mg/day. A confirmatory placebo-controlled trial is now planned.
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Affiliation(s)
| | - Bjoern O Schelter
- TauRx Therapeutics Ltd., Aberdeen, UK.,Institute for Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, UK
| | | | - Thomas C Baddeley
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | | | - Harish Ganesan
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Jeffrey Hammel
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Vesna Vuksanovic
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Roger T Staff
- Aberdeen Royal Infirmary, NHS Grampian, Aberdeen, UK
| | - Alison D Murray
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | | | - Damon J Wischik
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Computer Science and Technology, University of Cambridge, Cambridge, UK
| | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Serge Gauthier
- McGill Centre for Studies in Aging, Alzheimer's Disease Research Unit, and Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Jianping Jia
- Beijing Institute for Brain Disorders Alzheimer's Disease Centre, Beijing, China
| | | | | | | | | | - John M D Storey
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | - Charles R Harrington
- TauRx Therapeutics Ltd., Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Claude M Wischik
- TauRx Therapeutics Ltd., Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
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Berrocal M, Caballero-Bermejo M, Gutierrez-Merino C, Mata AM. Methylene Blue Blocks and Reverses the Inhibitory Effect of Tau on PMCA Function. Int J Mol Sci 2019; 20:ijms20143521. [PMID: 31323781 PMCID: PMC6678728 DOI: 10.3390/ijms20143521] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/05/2019] [Accepted: 07/11/2019] [Indexed: 12/24/2022] Open
Abstract
Methylene blue (MB) is a synthetic phenothiazine dye that, in the last years, has generated much debate about whether it could be a useful therapeutic drug for tau-related pathologies, such as Alzheimer’s disease (AD). However, the molecular mechanism of action is far from clear. Recently we reported that MB activates the plasma membrane Ca2+-ATPase (PMCA) in membranes from human and pig tissues and from cells cultures, and that it could protect against inactivation of PMCA by amyloid β-peptide (Aβ). The purpose of the present study is to further examine whether the MB could also modulate the inhibitory effect of tau, another key molecular marker of AD, on PMCA activity. By using kinetic assays in membranes from several tissues and cell cultures, we found that this phenothiazine was able to block and even to completely reverse the inhibitory effect of tau on PMCA. The results of this work point out that MB could mediate the toxic effect of tau related to the deregulation of calcium homeostasis by blocking the impairment of PMCA activity by tau. We then could conclude that MB could interfere with the toxic effects of tau by restoring the function of PMCA pump as a fine tuner of calcium homeostasis.
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Affiliation(s)
- Maria Berrocal
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Montaña Caballero-Bermejo
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Carlos Gutierrez-Merino
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Ana M Mata
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura and Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain.
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7
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de Castro AA, Soares FV, Pereira AF, Polisel DA, Caetano MS, Leal DHS, da Cunha EFF, Nepovimova E, Kuca K, Ramalho TC. Non-conventional compounds with potential therapeutic effects against Alzheimer’s disease. Expert Rev Neurother 2019; 19:375-395. [DOI: 10.1080/14737175.2019.1608823] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Alexandre A. de Castro
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
| | - Flávia V. Soares
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
| | - Ander F. Pereira
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
| | - Daniel A. Polisel
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
| | - Melissa S. Caetano
- Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Daniel H. S. Leal
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
- Department of Health Sciences, Federal University of Espírito Santo, São Mateus, Brazil
| | - Elaine F. F. da Cunha
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Kuca
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Teodorico C. Ramalho
- Laboratory of Molecular Modeling, Department of Chemistry, Federal University of Lavras, Lavras, Brazil
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
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Woehlck HJ, Boettcher BT, Lauer KK, Cronin DC, Hong JC, Zimmerman MA, Kim J, Selim M. Hydroxocobalamin for Vasoplegic Syndrome in Liver Transplantation. ACTA ACUST UNITED AC 2016; 7:247-250. [DOI: 10.1213/xaa.0000000000000398] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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9
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Kumar A, Singh A. A review on mitochondrial restorative mechanism of antioxidants in Alzheimer's disease and other neurological conditions. Front Pharmacol 2015; 6:206. [PMID: 26441662 PMCID: PMC4585235 DOI: 10.3389/fphar.2015.00206] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/07/2015] [Indexed: 12/13/2022] Open
Abstract
Neurodegenerative diseases are intricate in nature because of the involvement of the multiple pathophysiological events including mitochondrial dysfunction, neuroinflammation and oxidative stress. Alzheimer’s disease (AD) is a neurodegenerative disease explained by extracellular amyloid β deposits, intracellular neurofibrillary tangles and mitochondrial dysfunction. Increasing evidence has indicated that mitochondrial dysfunction displays significant role in the pathophysiological processes of AD. Mitochondrial dysfunction involves alterations in mitochondrial respiratory enzyme complex activities, oxidative stress, opening of permeability transition pore, and enhanced apoptosis. Various bioenergetics and antioxidants have been tried or under different investigational phase against AD and other neurodegenerative disorders (Parkinson’s disease, Huntington’s disease, and Amyotrophic lateral sclerosis) because of their complex and multiple site of action. These mitochondrial-targeting bioenergetics and antioxidant compounds such as coenzyme Q10, idebenone, creatine, mitoQ, mitovitE, MitoTEMPOL, latrepirdine, methylene blue, triterpenoids, SS peptides, curcumin, Ginkgo biloba, and omega-3 polyunsaturated fatty acids with potential efficacy in AD have been identified. Present review is intent to discuss mitochondrial restorative mechanisms of these bioenergetics and antioxidants as a potential alternative drug strategy for effective management of AD.
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Affiliation(s)
- Anil Kumar
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Study, Panjab University , Chandigarh, India
| | - Arti Singh
- Pharmacology Division, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Study, Panjab University , Chandigarh, India
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Delport A, Harvey BH, Petzer A, Petzer JP. Azure B and a synthetic structural analogue of methylene blue, ethylthioninium chloride, present with antidepressant-like properties. Life Sci 2014; 117:56-66. [DOI: 10.1016/j.lfs.2014.10.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 09/16/2014] [Accepted: 10/05/2014] [Indexed: 11/28/2022]
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Beckman ML, Pramod AB, Perley D, Henry LK. Stereoselective inhibition of serotonin transporters by antimalarial compounds. Neurochem Int 2013; 73:98-106. [PMID: 24161619 DOI: 10.1016/j.neuint.2013.10.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 10/11/2013] [Accepted: 10/15/2013] [Indexed: 10/26/2022]
Abstract
The serotonin (5-HT) transporter (SERT) is an integral membrane protein that functions to reuptake 5-HT released into the synapse following neurotransmission. This role serves an important regulatory mechanism in neuronal homeostasis. Previous studies have demonstrated that several clinically important antimalarial compounds inhibit serotonin (5-hydroxytryptamine, 5-HT) reuptake. In this study, we examined the details of antimalarial inhibition of 5-HT transport in both Drosophila (dSERT) and human SERT (hSERT) using electrophysiologic, biochemical and computational approaches. We found that the cinchona alkaloids quinidine and cinchonine, which have identical stereochemistry about carbons 8 and 9, exhibited the greatest inhibition of dSERT and hSERT transporter function whereas quinine and cinchonidine, enantiomers of quinidine and cinchonine, respectively, were weaker inhibitors of dSERT and hSERT. Furthermore, SERT mutations known to decrease the binding affinity of many antidepressants affected the cinchona alkaloids in a stereo-specific manner where the similar inhibitory profiles for quinine and cinchonidine (8S,9R) were distinct from quinidine and cinchonine (8R,9S). Small molecule docking studies with hSERT homology models predict that quinine and cinchonidine bind to the central 5-HT binding site (S1) whereas quinidine and cinchonine bind to the S2 site. Taken together, the data presented here support binding of cinchona alkaloids to two different sites on SERT defined by their stereochemistry which implies separate modes of transporter inhibition. Notably, the most potent antimalarial inhibitors of SERT appear to preferentially bind to the S2 site. Our findings provide important insight related to how this class of drugs can modulate the serotonergic system as well as identify compounds that may discriminate between the S1 and S2 binding sites and serve as lead compounds for novel SERT inhibitors.
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Affiliation(s)
- Matthew L Beckman
- Department of Biology, Augsburg College, 2211 Riverside Ave S, Minneapolis, MN 55454, United States.
| | - Akula Bala Pramod
- Department of Basic Sciences, University of North Dakota School of Medicine and Health Sciences, 501 North Columbia Road, Room 1700, Grand Forks, ND 58203, United States
| | - Danielle Perley
- Department of Basic Sciences, University of North Dakota School of Medicine and Health Sciences, 501 North Columbia Road, Room 1700, Grand Forks, ND 58203, United States
| | - L Keith Henry
- Department of Basic Sciences, University of North Dakota School of Medicine and Health Sciences, 501 North Columbia Road, Room 1700, Grand Forks, ND 58203, United States.
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Eckert GP, Renner K, Eckert SH, Eckmann J, Hagl S, Abdel-Kader RM, Kurz C, Leuner K, Muller WE. Mitochondrial Dysfunction—A Pharmacological Target in Alzheimer's Disease. Mol Neurobiol 2012; 46:136-50. [DOI: 10.1007/s12035-012-8271-z] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Accepted: 04/16/2012] [Indexed: 12/12/2022]
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