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Saavedra E, González-Chávez Z, Moreno-Sánchez R, Michels PA. Drug Target Selection for Trypanosoma cruzi Metabolism by Metabolic Control Analysis and Kinetic Modeling. Curr Med Chem 2019; 26:6652-6671. [DOI: 10.2174/0929867325666180917104242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 08/17/2018] [Accepted: 08/17/2018] [Indexed: 11/22/2022]
Abstract
In the search for therapeutic targets in the intermediary metabolism of trypanosomatids
the gene essentiality criterion as determined by using knock-out and knock-down genetic
strategies is commonly applied. As most of the evaluated enzymes/transporters have
turned out to be essential for parasite survival, additional criteria and approaches are clearly
required for suitable drug target prioritization. The fundamentals of Metabolic Control
Analysis (MCA; an approach in the study of control and regulation of metabolism) and kinetic
modeling of metabolic pathways (a bottom-up systems biology approach) allow quantification
of the degree of control that each enzyme exerts on the pathway flux (flux control coefficient)
and metabolic intermediate concentrations (concentration control coefficient). MCA
studies have demonstrated that metabolic pathways usually have two or three enzymes with
the highest control of flux; their inhibition has more negative effects on the pathway function
than inhibition of enzymes exerting low flux control. Therefore, the enzymes with the highest
pathway control are the most convenient targets for therapeutic intervention. In this review,
the fundamentals of MCA as well as experimental strategies to determine the flux control coefficients
and metabolic modeling are analyzed. MCA and kinetic modeling have been applied
to trypanothione metabolism in Trypanosoma cruzi and the model predictions subsequently
validated in vivo. The results showed that three out of ten enzyme reactions analyzed
in the T. cruzi anti-oxidant metabolism were the most controlling enzymes. Hence, MCA and
metabolic modeling allow a further step in target prioritization for drug development against
trypanosomatids and other parasites.
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Affiliation(s)
- Emma Saavedra
- Departamento de Bioquimica, Instituto Nacional de Cardiologia Ignacio Chavez. Mexico City, Mexico
| | - Zabdi González-Chávez
- Departamento de Bioquimica, Instituto Nacional de Cardiologia Ignacio Chavez. Mexico City, Mexico
| | - Rafael Moreno-Sánchez
- Departamento de Bioquimica, Instituto Nacional de Cardiologia Ignacio Chavez. Mexico City, Mexico
| | - Paul A.M. Michels
- Centre for Immunity, Infection and Evolution (CIIE) and Centre for Translational and Chemical Biology (CTCB), School of Biological Sciences, The University of Edinburgh, Edinburgh, Scotland
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2
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A critical review of the role of M 2PYK in the Warburg effect. Biochim Biophys Acta Rev Cancer 2019; 1871:225-239. [PMID: 30708038 PMCID: PMC6525063 DOI: 10.1016/j.bbcan.2019.01.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/14/2019] [Accepted: 01/14/2019] [Indexed: 12/17/2022]
Abstract
It is becoming generally accepted in recent literature that the Warburg effect in cancer depends on inhibition of M2PYK, the pyruvate kinase isozyme most commonly expressed in tumors. We remain skeptical. There continues to be a general lack of solid experimental evidence for the underlying idea that a bottle neck in aerobic glycolysis at the level of M2PYK results in an expanded pool of glycolytic intermediates (which are thought to serve as building blocks necessary for proliferation and growth of cancer cells). If a bottle neck at M2PYK exists, then the remarkable increase in lactate production by cancer cells is a paradox, particularly since a high percentage of the carbons of lactate originate from glucose. The finding that pyruvate kinase activity is invariantly increased rather than decreased in cancer undermines the logic of the M2PYK bottle neck, but is consistent with high lactate production. The "inactive" state of M2PYK in cancer is often described as a dimer (with reduced substrate affinity) that has dissociated from an active tetramer of M2PYK. Although M2PYK clearly dissociates easier than other isozymes of pyruvate kinase, it is not clear that dissociation of the tetramer occurs in vivo when ligands are present that promote tetramer formation. Furthermore, it is also not clear whether the dissociated dimer retains any activity at all. A number of non-canonical functions for M2PYK have been proposed, all of which can be challenged by the finding that not all cancer cell types are dependent on M2PYK expression. Additional in-depth studies of the Warburg effect and specifically of the possible regulatory role of M2PYK in the Warburg effect are needed.
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Smolders VF, Zodda E, Quax PHA, Carini M, Barberà JA, Thomson TM, Tura-Ceide O, Cascante M. Metabolic Alterations in Cardiopulmonary Vascular Dysfunction. Front Mol Biosci 2019; 5:120. [PMID: 30723719 PMCID: PMC6349769 DOI: 10.3389/fmolb.2018.00120] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 12/31/2018] [Indexed: 12/14/2022] Open
Abstract
Cardiovascular diseases (CVD) are the leading cause of death worldwide. CVD comprise a range of diseases affecting the functionality of the heart and blood vessels, including acute myocardial infarction (AMI) and pulmonary hypertension (PH). Despite their different causative mechanisms, both AMI and PH involve narrowed or blocked blood vessels, hypoxia, and tissue infarction. The endothelium plays a pivotal role in the development of CVD. Disruption of the normal homeostasis of endothelia, alterations in the blood vessel structure, and abnormal functionality are essential factors in the onset and progression of both AMI and PH. An emerging theory proposes that pathological blood vessel responses and endothelial dysfunction develop as a result of an abnormal endothelial metabolism. It has been suggested that, in CVD, endothelial cell metabolism switches to higher glycolysis, rather than oxidative phosphorylation, as the main source of ATP, a process designated as the Warburg effect. The evidence of these alterations suggests that understanding endothelial metabolism and mitochondrial function may be central to unveiling fundamental mechanisms underlying cardiovascular pathogenesis and to identifying novel critical metabolic biomarkers and therapeutic targets. Here, we review the role of the endothelium in the regulation of vascular homeostasis and we detail key aspects of endothelial cell metabolism. We also describe recent findings concerning metabolic endothelial cell alterations in acute myocardial infarction and pulmonary hypertension, their relationship with disease pathogenesis and we discuss the future potential of pharmacological modulation of cellular metabolism in the treatment of cardiopulmonary vascular dysfunction. Although targeting endothelial cell metabolism is still in its infancy, it is a promising strategy to restore normal endothelial functions and thus forestall or revert the development of CVD in personalized multi-hit interventions at the metabolic level.
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Affiliation(s)
- Valérie Françoise Smolders
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine (IBUB), Faculty of Biology, University of Barcelona, Barcelona, Spain
- Department of Pulmonary Medicine, Hospital Clínic-Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, Netherlands
- Department of Vascular Surgery, Leiden University Medical Center, Leiden, Netherlands
| | - Erika Zodda
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine (IBUB), Faculty of Biology, University of Barcelona, Barcelona, Spain
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Paul H. A. Quax
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, Netherlands
- Department of Vascular Surgery, Leiden University Medical Center, Leiden, Netherlands
| | - Marina Carini
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Joan Albert Barberà
- Department of Pulmonary Medicine, Hospital Clínic-Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBER) de Enfermedades Respiratorias, Madrid, Spain
| | - Timothy M. Thomson
- Institute for Molecular Biology of Barcelona, National Research Council (IBMB-CSIC), Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBER) de Enfermedades Hepáticas y Digestivas, Madrid, Spain
| | - Olga Tura-Ceide
- Department of Pulmonary Medicine, Hospital Clínic-Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBER) de Enfermedades Respiratorias, Madrid, Spain
| | - Marta Cascante
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine (IBUB), Faculty of Biology, University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBER) de Enfermedades Hepáticas y Digestivas, Madrid, Spain
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4
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Talevi A. Multi-target pharmacology: possibilities and limitations of the "skeleton key approach" from a medicinal chemist perspective. Front Pharmacol 2015; 6:205. [PMID: 26441661 PMCID: PMC4585027 DOI: 10.3389/fphar.2015.00205] [Citation(s) in RCA: 196] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 09/04/2015] [Indexed: 11/23/2022] Open
Abstract
Multi-target drugs have raised considerable interest in the last decade owing to their advantages in the treatment of complex diseases and health conditions linked to drug resistance issues. Prospective drug repositioning to treat comorbid conditions is an additional, overlooked application of multi-target ligands. While medicinal chemists usually rely on some version of the lock and key paradigm to design novel therapeutics, modern pharmacology recognizes that the mid- and long-term effects of a given drug on a biological system may depend not only on the specific ligand-target recognition events but also on the influence of the repeated administration of a drug on the cell gene signature. The design of multi-target agents usually imposes challenging restrictions on the topology or flexibility of the candidate drugs, which are briefly discussed in the present article. Finally, computational strategies to approach the identification of novel multi-target agents are overviewed.
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Affiliation(s)
- Alan Talevi
- Medicinal Chemistry, Department of Biological Sciences, Faculty of Exact Sciences, National University of La Plata , La Plata, Argentina
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Xu XD, Shao SX, Jiang HP, Cao YW, Wang YH, Yang XC, Wang YL, Wang XS, Niu HT. Warburg effect or reverse Warburg effect? A review of cancer metabolism. Oncol Res Treat 2015; 38:117-22. [PMID: 25792083 DOI: 10.1159/000375435] [Citation(s) in RCA: 140] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 01/22/2015] [Indexed: 11/19/2022]
Abstract
Cancer is a major threat to human health. A considerable amount of research has focused on elucidating the nature of cancer from its pathogenesis to treatment and prevention. Tumor cell metabolism has been considered a hallmark of cancer. Cancer cells differ from normal cells through unlimited cell division, and show a greater need for energy for their rapid growth and duplication. Research on glycometabolism, as the key point of energy metabolism, has played a unique role. In the 1920s, Warburg found that cancer cells prefer to produce adenosine triphosphate (ATP) by glycolysis, which is a less efficient pathway compared to oxidative phosphorylation. This striking discovery, called 'the Warburg effect', has influenced and guided the study of the mechanism and treatment of tumors for generations, but its causal relationship with cancer progression is still unclear. Some studies have now shown contradicting evidence and a new hypothesis, the reverse Warburg effect, has been put forward, in which cancer cells produce most of their ATP via glycolysis, even under aerobic conditions. In this review we discuss the new points concerning the energy metabolism of a tumor, as well as the current facts and perspectives.
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Affiliation(s)
- Xiao Dong Xu
- The Key Laboratory of Urology, Department of Urology, The Affiliated Hospital of Qingdao University, Qingdao, China
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Kell DB, Goodacre R. Metabolomics and systems pharmacology: why and how to model the human metabolic network for drug discovery. Drug Discov Today 2014; 19:171-82. [PMID: 23892182 PMCID: PMC3989035 DOI: 10.1016/j.drudis.2013.07.014] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 07/03/2013] [Accepted: 07/16/2013] [Indexed: 02/06/2023]
Abstract
Metabolism represents the 'sharp end' of systems biology, because changes in metabolite concentrations are necessarily amplified relative to changes in the transcriptome, proteome and enzyme activities, which can be modulated by drugs. To understand such behaviour, we therefore need (and increasingly have) reliable consensus (community) models of the human metabolic network that include the important transporters. Small molecule 'drug' transporters are in fact metabolite transporters, because drugs bear structural similarities to metabolites known from the network reconstructions and from measurements of the metabolome. Recon2 represents the present state-of-the-art human metabolic network reconstruction; it can predict inter alia: (i) the effects of inborn errors of metabolism; (ii) which metabolites are exometabolites, and (iii) how metabolism varies between tissues and cellular compartments. However, even these qualitative network models are not yet complete. As our understanding improves so do we recognise more clearly the need for a systems (poly)pharmacology.
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Affiliation(s)
- Douglas B Kell
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
| | - Royston Goodacre
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
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7
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Bazzani S, Hoppe A, Holzhütter HG. Network-based assessment of the selectivity of metabolic drug targets in Plasmodium falciparum with respect to human liver metabolism. BMC SYSTEMS BIOLOGY 2012; 6:118. [PMID: 22937810 PMCID: PMC3543272 DOI: 10.1186/1752-0509-6-118] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/23/2012] [Indexed: 11/10/2022]
Abstract
Background The search for new drug targets for antibiotics against Plasmodium falciparum, a major cause of human deaths, is a pressing scientific issue, as multiple resistance strains spread rapidly. Metabolic network-based analyses may help to identify those parasite’s essential enzymes whose homologous counterparts in the human host cells are either absent, non-essential or relatively less essential. Results Using the well-curated metabolic networks PlasmoNet of the parasite Plasmodium falciparum and HepatoNet1 of the human hepatocyte, the selectivity of 48 experimental antimalarial drug targets was analyzed. Applying in silico gene deletions, 24 of these drug targets were found to be perfectly selective, in that they were essential for the parasite but non-essential for the human cell. The selectivity of a subset of enzymes, that were essential in both models, was evaluated with the reduced fitness concept. It was, then, possible to quantify the reduction in functional fitness of the two networks under the progressive inhibition of the same enzymatic activity. Overall, this in silico analysis provided a selectivity ranking that was in line with numerous in vivo and in vitro observations. Conclusions Genome-scale models can be useful to depict and quantify the effects of enzymatic inhibitions on the impaired production of biomass components. From the perspective of a host-pathogen metabolic interaction, an estimation of the drug targets-induced consequences can be beneficial for the development of a selective anti-parasitic drug.
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Affiliation(s)
- Susanna Bazzani
- Institut für Biochemie, Charite-Universitätsmedizin, Berlin, Germany.
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8
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Geenen S, Taylor PN, Snoep JL, Wilson ID, Kenna JG, Westerhoff HV. Systems biology tools for toxicology. Arch Toxicol 2012; 86:1251-71. [PMID: 22569772 DOI: 10.1007/s00204-012-0857-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 04/12/2012] [Indexed: 12/18/2022]
Abstract
An important goal of toxicology is to understand and predict the adverse effects of drugs and other xenobiotics. For pharmaceuticals, such effects often emerge unexpectedly in man even when absent from trials in vitro and in animals. Although drugs and xenobiotics act on molecules, it is their perturbation of intracellular networks that matters. The tremendous complexity of these networks makes it difficult to understand the effects of xenobiotics on their ability to function. Because systems biology integrates data concerning molecules and their interactions into an understanding of network behaviour, it should be able to assist toxicology in this respect. This review identifies how in silico systems biology tools, such as kinetic modelling, and metabolic control, robustness and flux analyse, may indeed help understanding network-mediated toxicity. It also shows how these approaches function by implementing them vis-à-vis the glutathione network, which is important for the detoxification of reactive drug metabolites. The tools enable the appreciation of the steady state concept for the detoxification network and make it possible to simulate and then understand effects of perturbations of the macromolecules in the pathway that are counterintuitive. We review how a glutathione model has been used to explain the impact of perturbation of the pathway at various molecular sites, as would be the effect of single-nucleotide polymorphisms. We focus on how the mutations impact the levels of glutathione and of two candidate biomarkers of hepatic glutathione status. We conclude this review by sketching how the various systems biology tools may help in the various phases of drug development in the pharmaceutical industry.
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Affiliation(s)
- Suzanne Geenen
- Manchester Centre for Integrative Systems Biology, University of Manchester, UK
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9
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Abstract
Dupuytren's disease (DD) is an ill-defined fibroproliferative disorder of the palm of the hands leading to digital contracture. DD commonly occurs in individuals of northern European extraction. Cellular components and processes associated with DD pathogenesis include altered gene and protein expression of cytokines, growth factors, adhesion molecules, and extracellular matrix components. Histology has shown increased but varying levels of particular types of collagen, myofibroblasts and myoglobin proteins in DD tissue. Free radicals and localised ischaemia have been suggested to trigger the proliferation of DD tissue. Although the existing available biological information on DD may contain potentially valuable (though largely uninterpreted) information, the precise aetiology of DD remains unknown. Systems biology combines mechanistic modelling with quantitative experimentation in studies of networks and better understanding of the interaction of multiple components in disease processes. Adopting systems biology may be the ideal approach for future research in order to improve understanding of complex diseases of multifactorial origin. In this review, we propose that DD is a disease of several networks rather than of a single gene, and show that this accounts for the experimental observations obtained to date from a variety of sources. We outline how DD may be investigated more effectively by employing a systems biology approach that considers the disease network as a whole rather than focusing on any specific single molecule.
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Affiliation(s)
- Samrina Rehman
- Manchester Centre for Integrative Systems Biology, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK
| | - Royston Goodacre
- School of Chemistry, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK
| | - Philip J Day
- Quantitative Molecular Medicine Research, CIGMR, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK
| | - Ardeshir Bayat
- Plastic and Reconstructive Surgery Research, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK
| | - Hans V Westerhoff
- Manchester Centre for Integrative Systems Biology, Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, M1 7DN, UK
- Netherlands Institute for Systems Biology, VU University Amsterdam, NL-1081 HV, The Netherlands
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Coley AF, Dodson HC, Morris MT, Morris JC. Glycolysis in the african trypanosome: targeting enzymes and their subcellular compartments for therapeutic development. Mol Biol Int 2011; 2011:123702. [PMID: 22091393 PMCID: PMC3195984 DOI: 10.4061/2011/123702] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 02/16/2011] [Indexed: 12/16/2022] Open
Abstract
Subspecies of the African trypanosome, Trypanosoma brucei, which cause human African trypanosomiasis, are transmitted by the tsetse fly, with transmission-essential lifecycle stages occurring in both the insect vector and human host. During infection of the human host, the parasite is limited to using glycolysis of host sugar for ATP production. This dependence on glucose breakdown presents a series of targets for potential therapeutic development, many of which have been explored and validated as therapeutic targets experimentally. These include enzymes directly involved in glucose metabolism (e.g., the trypanosome hexokinases), as well as cellular components required for development and maintenance of the essential subcellular compartments that house the major part of the pathway, the glycosomes.
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Affiliation(s)
- April F Coley
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA
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Martinelli A, Henriques G, Cravo P, Hunt P. Whole genome re-sequencing identifies a mutation in an ABC transporter (mdr2) in a Plasmodium chabaudi clone with altered susceptibility to antifolate drugs. Int J Parasitol 2010; 41:165-71. [PMID: 20858498 PMCID: PMC3034870 DOI: 10.1016/j.ijpara.2010.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 07/27/2010] [Accepted: 08/13/2010] [Indexed: 12/16/2022]
Abstract
In malaria parasites, mutations in two genes of folate biosynthesis encoding dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) modify responses to antifolate therapies which target these enzymes. However, the involvement of other genes which modify the availability of exogenous folate, for example, has been proposed. Here, we used short-read whole-genome re-sequencing to determine the mutations in a clone of the rodent malaria parasite, Plasmodium chabaudi, which has altered susceptibility to both sulphadoxine and pyrimethamine. This clone bears a previously identified S106N mutation in dhfr and no mutation in dhps. Instead, three additional point mutations in genes on chromosomes 2, 13 and 14 were identified. The mutated gene on chromosome 13 (mdr2 K392Q) encodes an ABC transporter. Because Quantitative Trait Locus analysis previously indicated an association of genetic markers on chromosome 13 with responses to individual and combined antifolates, MDR2 is proposed to modulate antifolate responses, possibly mediated by the transport of folate intermediates.
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Affiliation(s)
- Axel Martinelli
- Centro de Malaria e Outras Doenças Tropicais/IHMT/UEI Biologia Molecular, Universidade Nova de Lisboa, Rua da Junqueira 96, 1349-008 Lisbon, Portugal.
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12
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Oosterveer MH, Grefhorst A, Groen AK, Kuipers F. The liver X receptor: control of cellular lipid homeostasis and beyond Implications for drug design. Prog Lipid Res 2010; 49:343-52. [PMID: 20363253 DOI: 10.1016/j.plipres.2010.03.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 02/22/2010] [Accepted: 03/19/2010] [Indexed: 11/30/2022]
Abstract
Liver X receptor (LXR) α and β are nuclear receptors that control cellular metabolism. LXRs modulate the expression of genes involved in cholesterol and lipid metabolism in response to changes in cellular cholesterol status. Because of their involvement in cholesterol homeostasis, LXRs have emerged as promising drug targets for anti-atherosclerotic therapies. In rodents, synthetic LXR agonists promote cellular cholesterol efflux, transport and excretion. As a result, the progression of atherosclerosis is halted. However, pharmacological LXR activation also induces hepatic steatosis and promotes the secretion of atherogenic triacylglycerol-rich VLDL particles by the liver, complicating the clinical application of LXR agonists. The more recently emerged roles of LXRs in fat tissue, pituitary and brain may have implications for treatment of obesity and Alzheimer disease. In addition to the improvements in atherosclerosis, LXR activation exerts beneficial effects on glucose control in mouse models of type 2 diabetes. Future therapeutic strategies aiming to exert beneficial effects on cholesterol and glucose homeostasis, while circumventing the undesired effects on hepatic lipid metabolism, should target specific LXR-mediated processes. Therefore, tissue and/or isotype-specific effects of LXR action need to be established. The consequences of combinatorial drug approaches and the identification of the co-regulatory networks involved in the LXR-mediated control of particular genes may contribute to development of novel LXR agonists. Finally, pathway analyses of LXR actions provide tools to evaluate and optimize the effectiveness of novel therapeutic strategies to prevent and/or treat metabolic diseases.
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Affiliation(s)
- Maaike H Oosterveer
- Department of Pediatrics, Center for Liver Digestive and Metabolic Diseases, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
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Drug-efficacy depends on the inhibitor type and the target position in a metabolic network—A systematic study. J Theor Biol 2008; 252:442-55. [DOI: 10.1016/j.jtbi.2007.09.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Revised: 09/14/2007] [Accepted: 09/18/2007] [Indexed: 01/29/2023]
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14
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Oxelmark E, Hornberg JJ. Finding the way in the jungle of kinase drug targets. DRUG DISCOVERY TODAY. TECHNOLOGIES 2007; 4:e89-e108. [PMID: 24139379 DOI: 10.1016/j.ddtec.2008.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Kinase inhibitors are developed for the treatment of various diseases. Because multiple factors control disease progression and kinases are part of large nonlinear networks, it is complicated to predict which kinase is the best to target. We substantiate the need for Systems Biology to assist in dealing with this complexity. Then, we discuss some of its contributions to kinase drug discovery with potential implications for the validation of kinases as drug targets and some of its present limitations.
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Affiliation(s)
- Ellinor Oxelmark
- Department of Molecular Pharmacology, Schering-Plough Research Institute, Oss, The Netherlands
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