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Colca JR, Tanis SP, Kletzien RF, Finck BN. Insulin sensitizers in 2023: lessons learned and new avenues for investigation. Expert Opin Investig Drugs 2023; 32:803-811. [PMID: 37755339 DOI: 10.1080/13543784.2023.2263369] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 09/22/2023] [Indexed: 09/28/2023]
Abstract
INTRODUCTION 'Insulin sensitizers' derived discoveries of the Takeda Company in 1970s. Pioglitazone remains the best in class with beneficial pleiotropic pharmacology, although use is limited by tolerability issues. Various attempts to expand out of this class assumed the primary molecular target was the transcription factor, PPARγ. Findings over the last 10 years have identified new targets of thiazolidinediones (TZDs) that should alter the drug discovery paradigm. AREAS COVERED We review structural classes of experimental insulin sensitizer drugs, some of which have attained limited approval in some markets. The TZD pioglitazone, originally approved in 1999 as a secondary treatment for type 2 diabetes, has demonstrated benefit in apparently diverse spectrums of disease from cardiovascular to neurological issues. New TZDs modulate a newly identified mitochondrial target (the mitochondrial pyruvate carrier) to reprogram metabolism and produce insulin sensitizing pharmacology devoid of tolerability issues. EXPERT OPINION Greater understanding of the mechanism of action of insulin sensitizing drugs can expand the rationale for the fields of treatment and potential for treatment combinations. This understanding can facilitate the registration and broader use of agents with that impact the pathophysiology that underlies chronic metabolic diseases as well as host responses to environmental insults including pathogens, insulin sensitizer, MPC, mitochondrial target, metabolic reprogramming, chronic and infectious disease.
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Affiliation(s)
| | | | | | - Brian N Finck
- Department of Medicine, Center for Human Nutrition, Washington University in St Louis, Euclid Ave, MO, USA
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2
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Ozaki K, Asato Y, Natsume N, Tojo S, Sumimoto S, Iwasaki A, Suenaga K, Teruya T. Differentiation-Promoting Effects of Okeaniamides A and B from an Okeania sp. Marine Cyanobacterium on Preadipocytes. JOURNAL OF NATURAL PRODUCTS 2023; 86:1564-1570. [PMID: 37307100 DOI: 10.1021/acs.jnatprod.3c00256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The linear lipopeptides okeaniamide A (1) and okeaniamide B (2) were isolated from an Okeania sp. marine cyanobacterium collected in Okinawa. The structures of these compounds were established by spectroscopic analyses, and the absolute configurations were elucidated based on a combination of chemical degradations, Marfey's analysis, and derivatization reactions. Okeaniamide A (1) and okeaniamide B (2) dose-dependently promoted the differentiation of mouse 3T3-L1 preadipocytes in the presence of insulin.
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Affiliation(s)
- Kaori Ozaki
- Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
| | - Yuka Asato
- Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
| | - Noriyuki Natsume
- Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
| | - Shunya Tojo
- Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
| | - Shimpei Sumimoto
- Department of Material and Life Chemistry, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
| | - Arihiro Iwasaki
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Kiyotake Suenaga
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Toshiaki Teruya
- Graduate School of Engineering and Science, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
- Faculty of Education, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
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3
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Colca JR, Finck BN. Metabolic Mechanisms Connecting Alzheimer's and Parkinson's Diseases: Potential Avenues for Novel Therapeutic Approaches. Front Mol Biosci 2022; 9:929328. [PMID: 35782864 PMCID: PMC9243557 DOI: 10.3389/fmolb.2022.929328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Alzheimer's (AD) and Parkinson's Diseases (PD) are common neurodegenerative disorders growing in incidence and prevalence and for which there are no disease-modifying treatments. While there are considerable complexities in the presentations of these diseases, the histological pictures of these pathologies, as well as several rare genetic predispositions for each, point to the involvement of maladaptive protein processing and inflammation. Importantly, the common presentations of AD and PD are connected to aging and to dysmetabolism, including common co-diagnosis of metabolic syndrome or diabetes. Examination of anti-diabetic therapies in preclinical models and in some observational clinical studies have suggested effectiveness of the first generation insulin sensitizer pioglitazone in both AD and PD. Recently, the mitochondrial pyruvate carrier (MPC) was shown to be a previously unrecognized target of pioglitazone. New insulin sensitizers are in development that can be dosed to full engagement of this previously unappreciated mitochondrial target. Here we review molecular mechanisms that connect modification of pyruvate metabolism with known liabilities of AD and PD. The mechanisms involve modification of autophagy, inflammation, and cell differentiation in various cell types including neurons, glia, macrophages, and endothelium. These observations have implications for the understanding of the general pathology of neurodegeneration and suggest general therapeutic approaches to disease modification.
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Affiliation(s)
- Jerry R. Colca
- Metabolic Solutions Development Company, Western Michigan University, Kalamazoo, MI, United States
| | - Brian N. Finck
- Washington University School of Medicine, St. Louis, MO, United States
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Colca JR, Scherer PE. The metabolic syndrome, thiazolidinediones, and implications for intersection of chronic and inflammatory disease. Mol Metab 2022; 55:101409. [PMID: 34863942 PMCID: PMC8688722 DOI: 10.1016/j.molmet.2021.101409] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 11/24/2021] [Accepted: 11/27/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Chronic disease appears connected to obesity. However, evidence suggests that chronic metabolic diseases are more specifically related to adipose dysfunction rather than to body weight itself. SCOPE OF REVIEW Further study of the first generation "insulin sensitizer" pioglitazone and molecules based on its structure suggests that is possible to decouple body weight from the metabolic dysfunction that drives adverse outcomes. The growing understanding of the mechanism of action of these agents together with advances in the pathophysiology of chronic metabolic disease offers a new approach to treat chronic conditions, such as type 2 diabetes, fatty liver disease, and their common organ and vascular sequelae. MAJOR CONCLUSIONS We hypothesize that treating adipocyte dysfunction with new insulin sensitizers might significantly impact the interface of infectious disease and chronic metabolic disease.
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Affiliation(s)
- Jerry R Colca
- Department of Biomedical Sciences, Western Michigan University School of Medicine, Kalamazoo, MI 49008, USA; Cirius Therapeutics, Kalamazoo, MI 49007, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA.
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Touaibia M, St-Coeur PD, Duff P, Faye DC, Pichaud N. 5-Benzylidene, 5-benzyl, and 3-benzylthiazolidine-2,4-diones as potential inhibitors of the mitochondrial pyruvate carrier: Effects on mitochondrial functions and survival in Drosophila melanogaster. Eur J Pharmacol 2021; 913:174627. [PMID: 34774497 DOI: 10.1016/j.ejphar.2021.174627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/29/2021] [Accepted: 11/08/2021] [Indexed: 01/17/2023]
Abstract
A series of thiazolidinediones (TZDs) were synthesized and screened for their effect on the mitochondrial respiration as well as on several mitochondrial respiratory system components of Drosophila melanogaster. Substituted and non-substituted 5-benzylidene and 5-benzylthiazolidine-2,4-diones were investigated. The effect of a substitution in position 3, at the nitrogen atom, of the thiozolidine heterocycle was also investigated. The designed TZDs were compared to UK5099, the most potent mitochondrial pyruvate carrier (MPC) inhibitor, in in vitro and in vivo tests. Compared to 5-benzylthiazolidine-2,4-diones 6-7 and 3-benzylthiazolidine-2,4-dione 8, 5-benzylidenethiazolidine-2,4-diones 2-5 showed more inhibitory capacity on mitochondrial respiration. 5-(4-Hydroxybenzylidene)thiazolidine-2,4-dione (3) and 5-(3-hydroxy-4-methoxybenzylidene)thiazolidine-2,4-dione (5) were among the best compounds that compared well with UK5099. Additionally, TZDs 3 and 5, showed no effects on the non-coupled respiration and weak effects on pathways using substrates such as proline, succinate, and G3P. 5-Benzylidenethiazolidine-2,4-dione 3 showed a positive effect on survival and lifespan when added to Drosophila standard and high fat diet. Interestingly, analog 3 completely reversed the effects of high fat diet on Drosophila longevity and induced metabolic changes which suggests an in vivo inhibition of MPC at the mitochondrial level.
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Affiliation(s)
- Mohamed Touaibia
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, Canada.
| | | | - Patrick Duff
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, Canada
| | - Diene Codou Faye
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, Canada
| | - Nicolas Pichaud
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB, Canada.
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Dixit G, Prabhu A. The pleiotropic peroxisome proliferator activated receptors: Regulation and therapeutics. Exp Mol Pathol 2021; 124:104723. [PMID: 34822814 DOI: 10.1016/j.yexmp.2021.104723] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/02/2021] [Accepted: 11/15/2021] [Indexed: 02/07/2023]
Abstract
The Peroxisome proliferator-activated receptors (PPARs) are key regulators of metabolic events in our body. Owing to their implication in maintenance of homeostasis, both PPAR agonists and antagonists assume therapeutic significance. Understanding the molecular mechanisms of each of the PPAR isotypes in the healthy body and during disease is crucial to exploiting their full therapeutic potential. This article is an attempt to present a rational analysis of the multifaceted therapeutic effects and underlying mechanisms of isotype-specific PPAR agonists, dual PPAR agonists, pan PPAR agonists as well as PPAR antagonists. A holistic understanding of the mechanistic dimensions of these key metabolic regulators will guide future efforts to identify novel molecules in the realm of metabolic, inflammatory and immunotherapeutic diseases.
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Affiliation(s)
- Gargi Dixit
- Department of Pharmaceutical Chemistry & Quality Assurance, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, India
| | - Arati Prabhu
- Department of Pharmaceutical Chemistry & Quality Assurance, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, India.
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Tanis SP, Colca JR, Parker TT, Artman GD, Larsen SD, McDonald WG, Gadwood RC, Kletzien RF, Zeller JB, Lee PH, Adams WJ. PPARγ-sparing thiazolidinediones as insulin sensitizers. Design, synthesis and selection of compounds for clinical development. Bioorg Med Chem 2018; 26:5870-5884. [DOI: 10.1016/j.bmc.2018.10.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/20/2018] [Accepted: 10/27/2018] [Indexed: 01/09/2023]
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Colca JR, McDonald WG, Adams WJ. MSDC-0602K, a metabolic modulator directed at the core pathology of non-alcoholic steatohepatitis. Expert Opin Investig Drugs 2018; 27:631-636. [PMID: 29950116 DOI: 10.1080/13543784.2018.1494153] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Non-alcoholic steatohepatitis (NASH) is a serious form of non-alcoholic fatty liver disease (NAFLD) for which there is no marketed treatments. NAFLD is initiated by excess intake of nutrients and recent evidence has pinpointed the mitochondrial pyruvate carrier (MPC) as a mediator of the nutritional overload signals. Areas covered: An overview is given of MSDC-0602K, a new agent in development that modulates the MPC and as such treats the symptoms of fatty liver including dysfunctional lipid metabolism, inflammation, and insulin resistance as well as the key liver pathology including fibrosis. METHODOLOGY The current evaluation is written from the direct experience of the authors and review of published literature using standard search techniques. Expert Opinion: The mechanism of action of MSDC-0602K appears to be suited for treatment of the NASH pathophysiology. An ongoing phase 2b dose-ranging trial should demonstrate whether or not MSDC-0602K has the potential to be a cornerstone metabolic therapy for the treatment of NASH.
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Vigueira PA, McCommis KS, Hodges WT, Schweitzer GG, Cole SL, Oonthonpan L, Taylor EB, McDonald WG, Kletzien RF, Colca JR, Finck BN. The beneficial metabolic effects of insulin sensitizers are not attenuated by mitochondrial pyruvate carrier 2 hypomorphism. Exp Physiol 2017; 102:985-999. [PMID: 28597936 DOI: 10.1113/ep086380] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/06/2017] [Indexed: 12/24/2022]
Abstract
NEW FINDINGS What is the central question of this study? The antidiabetic effects of thiazolidinedione (TZD) drugs may be mediated in part by a molecular interaction with the constituent proteins of the mitochondrial pyruvate carrier complex (MPC1 and MPC2). We examined the ability of a mutant mouse strain expressing an N-terminal truncation of MPC2 (Mpc2Δ16 mice) to respond to TZD treatment. What is the main finding and its importance? The response of Mpc2Δ16 mice to TZD treatment was not significantly different from that of wild-type C57BL6/J control animals, suggesting that the 16 N-terminal amino acids of MPC2 are dispensable for the effects of TZD treatment. Rosiglitazone and pioglitazone are thiazolidinedione (TZD) compounds that have been used clinically as insulin-sensitizing drugs and are generally believed to mediate their effects via activation of the peroxisome proliferator-activated receptor γ (PPARγ). Recent work has shown that it is possible to synthesize TZD compounds with potent insulin-sensitizing effects and markedly diminished affinity for PPARγ. Both clinically used TZDs and investigational PPARγ-sparing TZDs, such as MSDC-0602, interact with the mitochondrial pyruvate carrier (MPC) and inhibit its activity. The MPC complex is composed of two proteins, MPC1 and MPC2. Herein, we used mice expressing a hypomorphic MPC2 protein missing 16 amino acids in the N-terminus (Mpc2Δ16 mice) to determine the effects of these residues in mediating the insulin-sensitizing effects of TZDs in diet-induced obese mice. We found that both pioglitazone and MSDC-0602 elicited their beneficial metabolic effects, including improvement in glucose tolerance, attenuation of hepatic steatosis, reduction of adipose tissue inflammation and stimulation of adipocyte browning, in both wild-type and Mpc2Δ16 mice after high-fat diet feeding. In addition, truncation of MPC2 failed to attenuate the interaction between TZDs and the MPC in a bioluminescence resonance energy transfer-based assay or to affect the suppression of pyruvate-stimulated respiration in cells. Collectively, these data suggest that the interaction between TZDs and MPC2 is not affected by loss of the N-terminal 16 amino acids nor are these residues required for the insulin-sensitizing effects of these compounds.
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Affiliation(s)
- Patrick A Vigueira
- Department of Medicine, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Kyle S McCommis
- Department of Medicine, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Wesley T Hodges
- Department of Medicine, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - George G Schweitzer
- Department of Medicine, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Serena L Cole
- Metabolic Solutions Development Company, Kalamazoo, MI, 49007, USA
| | - Lalita Oonthonpan
- Department of Biochemistry and Fraternal Order of the Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA, 52240, USA
| | - Eric B Taylor
- Department of Biochemistry and Fraternal Order of the Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA, 52240, USA
| | | | - Rolf F Kletzien
- Metabolic Solutions Development Company, Kalamazoo, MI, 49007, USA
| | - Jerry R Colca
- Metabolic Solutions Development Company, Kalamazoo, MI, 49007, USA
| | - Brian N Finck
- Department of Medicine, Washington University School of Medicine, St Louis, MO, 63110, USA
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Colca JR. The TZD insulin sensitizer clue provides a new route into diabetes drug discovery. Expert Opin Drug Discov 2015; 10:1259-70. [DOI: 10.1517/17460441.2015.1100164] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wright MB, Bortolini M, Tadayyon M, Bopst M. Minireview: Challenges and opportunities in development of PPAR agonists. Mol Endocrinol 2014; 28:1756-68. [PMID: 25148456 PMCID: PMC5414793 DOI: 10.1210/me.2013-1427] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 08/08/2014] [Indexed: 01/06/2023] Open
Abstract
The clinical impact of the fibrate and thiazolidinedione drugs on dyslipidemia and diabetes is driven mainly through activation of two transcription factors, peroxisome proliferator-activated receptors (PPAR)-α and PPAR-γ. However, substantial differences exist in the therapeutic and side-effect profiles of specific drugs. This has been attributed primarily to the complexity of drug-target complexes that involve many coregulatory proteins in the context of specific target gene promoters. Recent data have revealed that some PPAR ligands interact with other non-PPAR targets. Here we review concepts used to develop new agents that preferentially modulate transcriptional complex assembly, target more than one PPAR receptor simultaneously, or act as partial agonists. We highlight newly described on-target mechanisms of PPAR regulation including phosphorylation and nongenomic regulation. We briefly describe the recently discovered non-PPAR protein targets of thiazolidinediones, mitoNEET, and mTOT. Finally, we summarize the contributions of on- and off-target actions to select therapeutic and side effects of PPAR ligands including insulin sensitivity, cardiovascular actions, inflammation, and carcinogenicity.
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Affiliation(s)
- Matthew B Wright
- F. Hoffmann-La Roche Pharmaceuticals (M.B.W., M.Bor., M.Bop.), CH-4070 Basel, Switzerland; and MediTech Media (M.T.), London EC1V 9AZ, United Kingdom
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Colca JR, McDonald WG, Kletzien RF. Mitochondrial target of thiazolidinediones. Diabetes Obes Metab 2014; 16:1048-54. [PMID: 24774061 DOI: 10.1111/dom.12308] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/17/2014] [Accepted: 04/22/2014] [Indexed: 12/11/2022]
Abstract
Insulin-sensitizing thiazolidinediones exert a pleiotropic pharmacology with therapeutic potential in a number of disease states ranging from metabolic syndrome and diabetes to neurodegeneration and cancer. A growing understanding of their mechanism of action, working from the site of their binding in the mitochondrion, provides insight into the mechanism of action of the insulin sensitizers and the reasons for their pleiotropic pharmacology. This review helps to frame the direction of future work that should be helpful in setting a new direction for the discovery and development of new, more useful therapeutic agents for metabolic disease.
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Affiliation(s)
- J R Colca
- Metabolic Solutions Development Company, Kalamazoo, MI, USA
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Tamir S, Paddock ML, Darash-Yahana-Baram M, Holt SH, Sohn YS, Agranat L, Michaeli D, Stofleth JT, Lipper CH, Morcos F, Cabantchik IZ, Onuchic JN, Jennings PA, Mittler R, Nechushtai R. Structure-function analysis of NEET proteins uncovers their role as key regulators of iron and ROS homeostasis in health and disease. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1294-315. [PMID: 25448035 DOI: 10.1016/j.bbamcr.2014.10.014] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 10/01/2014] [Accepted: 10/16/2014] [Indexed: 12/31/2022]
Abstract
A novel family of 2Fe-2S proteins, the NEET family, was discovered during the last decade in numerous organisms, including archea, bacteria, algae, plant and human; suggesting an evolutionary-conserved function, potentially mediated by their CDGSH Iron-Sulfur Domain. In human, three NEET members encoded by the CISD1-3 genes were identified. The structures of CISD1 (mitoNEET, mNT), CISD2 (NAF-1), and the plant At-NEET uncovered a homodimer with a unique "NEET fold", as well as two distinct domains: a beta-cap and a 2Fe-2S cluster-binding domain. The 2Fe-2S clusters of NEET proteins were found to be coordinated by a novel 3Cys:1His structure that is relatively labile compared to other 2Fe-2S proteins and is the reason of the NEETs' clusters could be transferred to apo-acceptor protein(s) or mitochondria. Positioned at the protein surface, the NEET's 2Fe-2S's coordinating His is exposed to protonation upon changes in its environment, potentially suggesting a sensing function for this residue. Studies in different model systems demonstrated a role for NAF-1 and mNT in the regulation of cellular iron, calcium and ROS homeostasis, and uncovered a key role for NEET proteins in critical processes, such as cancer cell proliferation and tumor growth, lipid and glucose homeostasis in obesity and diabetes, control of autophagy, longevity in mice, and senescence in plants. Abnormal regulation of NEET proteins was consequently found to result in multiple health conditions, and aberrant splicing of NAF-1 was found to be a causative of the neurological genetic disorder Wolfram Syndrome 2. Here we review the discovery of NEET proteins, their structural, biochemical and biophysical characterization, and their most recent structure-function analyses. We additionally highlight future avenues of research focused on NEET proteins and propose an essential role for NEETs in health and disease. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
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Affiliation(s)
- Sagi Tamir
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Mark L Paddock
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093, USA
| | - Merav Darash-Yahana-Baram
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Sarah H Holt
- Department of Biology, University of North Texas, Denton, TX 76203, USA
| | - Yang Sung Sohn
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Lily Agranat
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Dorit Michaeli
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Jason T Stofleth
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093, USA
| | - Colin H Lipper
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093, USA
| | - Faruck Morcos
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77050, USA; Department of Physics and Astronomy, Rice University, Houston, TX 77050, USA; Department of Chemistry, Rice University, Houston, TX 77050, USA; Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77050, USA
| | - Ioav Z Cabantchik
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel
| | - Jose' N Onuchic
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77050, USA; Department of Physics and Astronomy, Rice University, Houston, TX 77050, USA; Department of Chemistry, Rice University, Houston, TX 77050, USA; Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77050, USA
| | - Patricia A Jennings
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093, USA
| | - Ron Mittler
- Department of Biology, University of North Texas, Denton, TX 76203, USA
| | - Rachel Nechushtai
- The Alexander Silberman Life Science Institute and the Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel.
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Colca JR, Tanis SP, McDonald WG, Kletzien RF. Insulin sensitizers in 2013: new insights for the development of novel therapeutic agents to treat metabolic diseases. Expert Opin Investig Drugs 2013; 23:1-7. [DOI: 10.1517/13543784.2013.839659] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Jerry R Colca
- Metabolic Solutions Development Company,
161 E. Michigan Ave, Kalamazoo, 49007, USA
| | - Steven P Tanis
- PharmaChem Consulting LLC,
1750 Oriole Ct, Carlsbad, 92011, United States
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15
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Colca JR, McDonald WG, Cavey GS, Cole SL, Holewa DD, Brightwell-Conrad AS, Wolfe CL, Wheeler JS, Coulter KR, Kilkuskie PM, Gracheva E, Korshunova Y, Trusgnich M, Karr R, Wiley SE, Divakaruni AS, Murphy AN, Vigueira PA, Finck BN, Kletzien RF. Identification of a mitochondrial target of thiazolidinedione insulin sensitizers (mTOT)--relationship to newly identified mitochondrial pyruvate carrier proteins. PLoS One 2013; 8:e61551. [PMID: 23690925 PMCID: PMC3655167 DOI: 10.1371/journal.pone.0061551] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 03/10/2013] [Indexed: 01/01/2023] Open
Abstract
Thiazolidinedione (TZD) insulin sensitizers have the potential to effectively treat a number of human diseases, however the currently available agents have dose-limiting side effects that are mediated via activation of the transcription factor PPARγ. We have recently shown PPARγ-independent actions of TZD insulin sensitizers, but the molecular target of these molecules remained to be identified. Here we use a photo-catalyzable drug analog probe and mass spectrometry-based proteomics to identify a previously uncharacterized mitochondrial complex that specifically recognizes TZDs. These studies identify two well-conserved proteins previously known as brain protein 44 (BRP44) and BRP44 Like (BRP44L), which recently have been renamed Mpc2 and Mpc1 to signify their function as a mitochondrial pyruvate carrier complex. Knockdown of Mpc1 or Mpc2 in Drosophila melanogaster or pre-incubation with UK5099, an inhibitor of pyruvate transport, blocks the crosslinking of mitochondrial membranes by the TZD probe. Knockdown of these proteins in Drosophila also led to increased hemolymph glucose and blocked drug action. In isolated brown adipose tissue (BAT) cells, MSDC-0602, a PPARγ-sparing TZD, altered the incorporation of 13C-labeled carbon from glucose into acetyl CoA. These results identify Mpc1 and Mpc2 as components of the mitochondrial target of TZDs (mTOT) and suggest that understanding the modulation of this complex, which appears to regulate pyruvate entry into the mitochondria, may provide a viable target for insulin sensitizing pharmacology.
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Affiliation(s)
- Jerry R Colca
- Metabolic Solutions Development Company, Kalamazoo, Michigan, United States of America.
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16
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Thiazolidinediones are acute, specific inhibitors of the mitochondrial pyruvate carrier. Proc Natl Acad Sci U S A 2013; 110:5422-7. [PMID: 23513224 DOI: 10.1073/pnas.1303360110] [Citation(s) in RCA: 220] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Facilitated pyruvate transport across the mitochondrial inner membrane is a critical step in carbohydrate, amino acid, and lipid metabolism. We report that clinically relevant concentrations of thiazolidinediones (TZDs), a widely used class of insulin sensitizers, acutely and specifically inhibit mitochondrial pyruvate carrier (MPC) activity in a variety of cell types. Respiratory inhibition was overcome with methyl pyruvate, localizing the effect to facilitated pyruvate transport, and knockdown of either paralog, MPC1 or MPC2, decreased the EC50 for respiratory inhibition by TZDs. Acute MPC inhibition significantly enhanced glucose uptake in human skeletal muscle myocytes after 2 h. These data (i) report that clinically used TZDs inhibit the MPC, (ii) validate that MPC1 and MPC2 are obligatory components of facilitated pyruvate transport in mammalian cells, (iii) indicate that the acute effect of TZDs may be related to insulin sensitization, and (iv) establish mitochondrial pyruvate uptake as a potential therapeutic target for diseases rooted in metabolic dysfunction.
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17
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Clinical proof-of-concept study with MSDC-0160, a prototype mTOT-modulating insulin sensitizer. Clin Pharmacol Ther 2013; 93:352-9. [PMID: 23462886 PMCID: PMC3604641 DOI: 10.1038/clpt.2013.10] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
It may be possible to achieve insulin sensitivity through the recently identified mitochondrial target of thiazolidinediones (mTOT), thereby avoiding peroxisome proliferator–activated receptor-γ (PPAR-γ)-dependent side effects. In this phase IIb clinical trial, 258 patients with type 2 diabetes completed a 12-week protocol with 50, 100, or 150 mg of MSDC-0160 (an mTOT modulator), 45 mg pioglitazone HCl (a PPAR-γ agonist), or a placebo. The two active treatments lowered fasting glucose levels to the same extent. The decreases in glycated hemoglobin (HbA1c) observed with the two higher doses of MSDC-0160 were not different from those associated with pioglitazone. By contrast, fluid retention as evidenced by reduction in hematocrit, red blood cells, and total hemoglobin was 50% less in the MSDC-0160–treated groups. There was also a smaller increase in high-molecular-weight (HMW) adiponectin with MSDC-0160 than with pioglitazone (P < 0.0001), suggesting that MSDC-0160 produces less expansion of white adipose tissue. Thus, mTOT modulators may have glucose-lowering effects similar to those of pioglitazone but without the adverse effects associated with PPAR-γ agonists.
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18
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Chen Z, Vigueira PA, Chambers KT, Hall AM, Mitra MS, Qi N, McDonald WG, Colca JR, Kletzien RF, Finck BN. Insulin resistance and metabolic derangements in obese mice are ameliorated by a novel peroxisome proliferator-activated receptor γ-sparing thiazolidinedione. J Biol Chem 2012; 287:23537-48. [PMID: 22621923 PMCID: PMC3390629 DOI: 10.1074/jbc.m112.363960] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/22/2012] [Indexed: 11/06/2022] Open
Abstract
Currently approved thiazolidinediones (TZDs) are effective insulin-sensitizing drugs that may have efficacy for treatment of a variety of metabolic and inflammatory diseases, but their use is limited by side effects that are mediated through ectopic activation of the peroxisome proliferator-activated receptor γ (PPARγ). Emerging evidence suggests that the potent anti-diabetic efficacy of TZDs can be separated from the ability to serve as ligands for PPARγ. A novel TZD analog (MSDC-0602) with very low affinity for binding and activation of PPARγ was evaluated for its effects on insulin resistance in obese mice. MSDC-0602 treatment markedly improved several measures of multiorgan insulin sensitivity, adipose tissue inflammation, and hepatic metabolic derangements, including suppressing hepatic lipogenesis and gluconeogenesis. These beneficial effects were mediated at least in part via direct actions on hepatocytes and were preserved in hepatocytes from liver-specific PPARγ(-/-) mice, indicating that PPARγ was not required to suppress these pathways. In conclusion, the beneficial pharmacology exhibited by MSDC-0602 on insulin sensitivity suggests that PPARγ-sparing TZDs are effective for treatment of type 2 diabetes with reduced risk of PPARγ-mediated side effects.
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Affiliation(s)
- Zhouji Chen
- From the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Patrick A. Vigueira
- From the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Kari T. Chambers
- From the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Angela M. Hall
- From the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Mayurranjan S. Mitra
- From the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Nathan Qi
- the Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, and
| | | | - Jerry R. Colca
- Metabolic Solutions Development Company, Kalamazoo, Michigan 49007
| | - Rolf F. Kletzien
- Metabolic Solutions Development Company, Kalamazoo, Michigan 49007
| | - Brian N. Finck
- From the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
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Zuris JA, Ali SS, Yeh H, Nguyen TA, Nechushtai R, Paddock ML, Jennings PA. NADPH inhibits [2Fe-2S] cluster protein transfer from diabetes drug target MitoNEET to an apo-acceptor protein. J Biol Chem 2012; 287:11649-55. [PMID: 22351774 DOI: 10.1074/jbc.m111.319731] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
MitoNEET (mNT) is the founding member of the recently discovered CDGSH family of [2Fe-2S] proteins capable of [2Fe-2S] cluster transfer to apo-acceptor proteins. It is a target of the thiazolidinedione (TZD) class of anti-diabetes drugs whose binding modulate both electron transfer and cluster transfer properties. The [2Fe-2S] cluster in mNT is destabilized upon binding of NADPH, which leads to loss of the [2Fe-2S] cluster to the solution environment. Because mNT is capable of transferring [2Fe-2S] clusters to apo-acceptor proteins, we sought to determine whether NADPH binding also affects cluster transfer. We show that NADPH inhibits transfer of the [2Fe-2S] cluster to an apo-acceptor protein with an inhibition constant (K(i)) of 200 μm, which reflects that of NADPH concentrations expected under physiological conditions. In addition, we determined that the strictly conserved cluster interacting residue Asp-84 in the CDGSH domain is necessary for the NADPH-dependent inhibition of [2Fe-2S] cluster transfer. The most critical cellular function of NADPH is in the maintenance of a pool of reducing equivalents, which is essential to counteract oxidative damage. Taken together, our findings suggest that NADPH can regulate both mNT [2Fe-2S] cluster levels in the cell as well as the ability of the protein to transfer [2Fe-2S] clusters to cytosolic or mitochondrial acceptors.
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Affiliation(s)
- John A Zuris
- Department of Chemistry, University of California at San Diego, La Jolla, California 92093, USA
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20
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Colca JR, Feinstein DL. Altering Mitochondrial Dysfunction as an Approach to Treating Alzheimer’s Disease. CURRENT STATE OF ALZHEIMER'S DISEASE RESEARCH AND THERAPEUTICS 2012; 64:155-76. [DOI: 10.1016/b978-0-12-394816-8.00005-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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21
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Facile transfer of [2Fe-2S] clusters from the diabetes drug target mitoNEET to an apo-acceptor protein. Proc Natl Acad Sci U S A 2011; 108:13047-52. [PMID: 21788481 DOI: 10.1073/pnas.1109986108] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
MitoNEET (mNT) is an outer mitochondrial membrane target of the thiazolidinedione diabetes drugs with a unique fold and a labile [2Fe-2S] cluster. The rare 1-His and 3-Cys coordination of mNT's [2Fe-2S] leads to cluster lability that is strongly dependent on the presence of the single histidine ligand (His87). These properties of mNT are similar to known [2Fe-2S] shuttle proteins. Here we investigated whether mNT is capable of cluster transfer to acceptor protein(s). Facile [2Fe-2S] cluster transfer is observed between oxidized mNT and apo-ferredoxin (a-Fd) using UV-VIS spectroscopy and native-PAGE, as well as with a mitochondrial iron detection assay in cells. The transfer is unidirectional, proceeds to completion, and occurs with a second-order-reaction rate that is comparable to known iron-sulfur transfer proteins. Mutagenesis of His87 with Cys (H87C) inhibits transfer of the [2Fe-2S] clusters to a-Fd. This inhibition is beyond that expected from increased cluster kinetic stability, as the equivalently stable Lys55 to Glu (K55E) mutation did not inhibit transfer. The H87C mutant also failed to transfer its iron to mitochondria in HEK293 cells. The diabetes drug pioglitazone inhibits iron transfer from WT mNT to mitochondria, indicating that pioglitazone affects a specific property, [2Fe-2S] cluster transfer, in the cellular environment. This finding is interesting in light of the role of iron overload in diabetes. Our findings suggest a likely role for mNT in [2Fe-2S] and/or iron transfer to acceptor proteins and support the idea that pioglitazone's antidiabetic mode of action may, in part, be to inhibit transfer of mNT's [2Fe-2S] cluster.
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Doshi LS, Brahma MK, Bahirat UA, Dixit AV, Nemmani KVS. Discovery and development of selective PPAR gamma modulators as safe and effective antidiabetic agents. Expert Opin Investig Drugs 2010; 19:489-512. [PMID: 20367191 DOI: 10.1517/13543781003640169] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
IMPORTANCE OF THE FIELD PPARgamma full agonists (pioglitazone and rosiglitazone) are the mainstay drugs for the treatment of type 2 diabetes; however, mechanism-based side effects have limited their full therapeutic potential. In recent years, much progress has been achieved in the discovery and development of selective PPARgamma modulators (SPPARgammaMs) as safer alternatives to PPARgamma full agonists. AREAS COVERED IN THIS REVIEW This review focuses on the preclinical and clinical data of all the SPPARgammaMs discovered so far, retrieved by searching PubMed, Prous Integrity database and company news updates from 1999 to date. WHAT THE READER WILL GAIN Here we thoroughly discuss SPPARgammaMs' mode of action, briefly examine new ways to identify superior SPPARgammaMs, and finally, compare and contrast the pharmacological and safety profile of various agents. TAKE HOME MESSAGE The preclinical and clinical findings clearly suggest that selective PPARgamma modulators have the potential to become the next generation of PPARgamma agonists: effective insulin sensitizers with a superior safety profile to that of PPARgamma full agonists.
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Affiliation(s)
- Lalit S Doshi
- Department of Pharmacology, Piramal Life Sciences Limited, 1 Nirlon Complex, Goregaon (E), Mumbai - 400 063, India
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23
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Schulman IG. Nuclear receptors as drug targets for metabolic disease. Adv Drug Deliv Rev 2010; 62:1307-15. [PMID: 20655343 DOI: 10.1016/j.addr.2010.07.002] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 07/06/2010] [Accepted: 07/14/2010] [Indexed: 01/02/2023]
Abstract
Nuclear hormone receptors comprise a superfamily of ligand-activated transcription factors that control development, differentiation, and homeostasis. Over the last 15 years a growing number of nuclear receptors have been identified that coordinate genetic networks regulating lipid metabolism and energy utilization. Several of these receptors directly sample the levels of metabolic intermediates including fatty acids and cholesterol derivatives and use this information to regulate the synthesis, transport, and breakdown of the metabolite of interest. In contrast, other family members sense metabolic activity via the presence or absence of interacting proteins. The ability of these nuclear receptors to impact metabolism will be discussed and the challenges facing drug discovery efforts for this class of targets will be highlighted.
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24
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Colca JR, Kletzien RF. Current and emerging strategies for treating dyslipidemia and macrovascular disease. ADVANCES IN PHARMACOLOGY 2009; 57:237-51. [PMID: 20230763 DOI: 10.1016/s1054-3589(08)57006-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
Statins, inhibitors of hydroxymethylglutaryl CoA (HMG-CoA) reductase, have been in clinical use for over 20 years. The widespread use of these agents has left doubt of the efficacy of cholesterol-lowering therapy to prevent cardiovascular disease. In spite of the widespread use of these agents and the successful lowering of circulating cholesterol together with reduction of cardiovascular-related deaths, there is consensus that further improvements in therapy are needed. Cardiovascular disease remains a major cause of premature death and continues to exert an extensive drain on the health-care costs. This chapter outlines some of the emerging strategies for discovering and developing novel treatments of dyslipidemia and macrovascular disease. Mechanisms considered include alternate ways to lower total cholesterol through inhibition of synthesis, limitation of absorption, or recycling. Other approaches include the modification of circulating forms of cholesterol and changes in gene expression at the key sites of storage, utilization, and pathology. The next successful strategy will likely be one that works well in concert with existing statins.
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Affiliation(s)
- Jerry R Colca
- Metabolic Solutions Development Company, 125 S. Kalamazoo Mall #202, Kalamazoo, Michigan 49007, USA
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25
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Huang HJ, Schulman IG. Regulation of metabolism by nuclear hormone receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2009; 87:1-51. [PMID: 20374700 DOI: 10.1016/s1877-1173(09)87001-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The worldwide epidemic of metabolic disease indicates that a better understanding of the pathways contributing to the pathogenesis of this constellation of diseases need to be determined. Nuclear hormone receptors comprise a superfamily of ligand-activated transcription factors that control development, differentiation, and metabolism. Over the last 15 years a growing number of nuclear receptors have been identified that coordinate genetic networks regulating lipid metabolism and energy utilization. Several of these receptors directly sample the levels of metabolic intermediates and use this information to regulate the synthesis, transport, and breakdown of the metabolite of interest. In contrast, other family members sense metabolic activity via the presence or absence of interacting proteins. The ability of these nuclear receptors to impact metabolism and inflammation will be discussed and the potential of each receptor subfamily to serve as drug targets for metabolic disease will be highlighted.
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Affiliation(s)
- Huey-Jing Huang
- Department of Biology, Exelixis Inc., 4757 Nexus Centre Drive, San Diego, California 92121, USA
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26
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Abstract
Sulphonylureas (SUs) and biguanides (metformin) are the current mainstays in the treatment of type 2 diabetes (T2DM) and represent the most commonly used oral hypoglycaemic agents (OHAs). In recent years, a variety of new OHAs have become available, including thiazolidinediones, glinides, alpha-glucosidase inhibitors, glucagon-like peptide-1 agonists, amylin analogues and dipeptidyl peptidase-IV inhibitors, providing physicians with a larger therapeutic catalogue than ever before. The traditional drugs metformin and SUs have an established safety profile through long-term use. However, long-term clinical trials and routine use are lacking for many of the new agents, and some potentially serious side effects have been reported with several of these compounds. Until adequate data is obtained, it is difficult to assess the risk-benefit ratio of these agents in relation to the traditional drugs. Until that becomes fully documented, it may be wise to start pharmacologic treatment of patients on an individual basis, weighing the benefits and costs of each medication. Thus, there remains a place for well-established drugs that have a proven safety record and are supported by years of clinical use for the treatment of T2DM.
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Affiliation(s)
- J Philippe
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University Hospital, Geneva, Switzerland.
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27
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Colca JR. 67 th annual meeting of the American Diabetes Association. Expert Opin Investig Drugs 2007; 16:1735-9. [PMID: 17922635 DOI: 10.1517/13543784.16.10.1735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The 67 th meeting of the American Diabetes Association was held in Chicago on 22 - 26 June. This annual meeting continues to grow in size and scope and is a unique combination of basic science and medical science but also incorporates all aspects of healthcare and pharmaceutical business relating to the treatment of diabetes. The meeting was composed of general sessions, symposia summarizing the status of various fields of study and medical practice, together with both oral and poster presentations of new, previously unpublished research. The abstracts are published in Diabetes and a collection of the information can be found online with very useful summaries from the final day. These contain personalized summaries of key findings of the meetings as seen by key researches in the field. In this Meeting Highlights article, the key take-away messages are summarized from the author's point of view.
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Affiliation(s)
- Jerry R Colca
- Metabolic Solutions Development Co., 125 S. Kalamazoo Mall #202, Kalamazoo, Michigan 49007, USA.
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28
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Colca JR. Discontinued drugs in 2006: renal, endocrine and metabolic drugs. Expert Opin Investig Drugs 2007; 16:1517-23. [DOI: 10.1517/13543784.16.10.1517] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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29
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Paddock ML, Wiley SE, Axelrod HL, Cohen AE, Roy M, Abresch EC, Capraro D, Murphy AN, Nechushtai R, Dixon JE, Jennings PA. MitoNEET is a uniquely folded 2Fe 2S outer mitochondrial membrane protein stabilized by pioglitazone. Proc Natl Acad Sci U S A 2007; 104:14342-7. [PMID: 17766440 PMCID: PMC1963346 DOI: 10.1073/pnas.0707189104] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2007] [Indexed: 12/15/2022] Open
Abstract
Iron-sulfur (Fe-S) proteins are key players in vital processes involving energy homeostasis and metabolism from the simplest to most complex organisms. We report a 1.5 A x-ray crystal structure of the first identified outer mitochondrial membrane Fe-S protein, mitoNEET. Two protomers intertwine to form a unique dimeric structure that constitutes a new fold to not only the approximately 650 reported Fe-S protein structures but also to all known proteins. We name this motif the NEET fold. The protomers form a two-domain structure: a beta-cap domain and a cluster-binding domain that coordinates two acid-labile 2Fe-2S clusters. Binding of pioglitazone, an insulin-sensitizing thiazolidinedione used in the treatment of type 2 diabetes, stabilizes the protein against 2Fe-2S cluster release. The biophysical properties of mitoNEET suggest that it may participate in a redox-sensitive signaling and/or in Fe-S cluster transfer.
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Affiliation(s)
| | | | - Herbert L. Axelrod
- Stanford Synchrotron Radiation Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025; and
| | - Aina E. Cohen
- Stanford Synchrotron Radiation Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025; and
| | | | | | | | | | - Rachel Nechushtai
- Department of Plant and Environmental Sciences, The Wolfson Centre for Applied Structural Biology, Hebrew University of Jerusalem, Givat Ram 91904, Israel
| | - Jack E. Dixon
- Pharmacology
- Chemistry and Biochemistry, and
- Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093
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30
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Lin J, Zhou T, Ye K, Wang J. Crystal structure of human mitoNEET reveals distinct groups of iron sulfur proteins. Proc Natl Acad Sci U S A 2007; 104:14640-5. [PMID: 17766439 PMCID: PMC1976232 DOI: 10.1073/pnas.0702426104] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
MitoNEET is a protein of unknown function present in the mitochondrial membrane that was recently shown to bind specifically the antidiabetic drug pioglizatone. Here, we report the crystal structure of the soluble domain (residues 32-108) of human mitoNEET at 1.8-A resolution. The structure reveals an intertwined homodimer, and each subunit was observed to bind a [2Fe-2S] cluster. The [2Fe-2S] ligation pattern of three cysteines and one histidine differs from the known pattern of four cysteines in most cases or two cysteines and two histidines as observed in Rieske proteins. The [2Fe-2S] cluster is packed in a modular structure formed by 17 consecutive residues. The cluster-binding motif is conserved in at least seven distinct groups of proteins from bacteria, archaea, and eukaryotes, which show a consensus sequence of (hb)-C-X(1)-C-X(2)-(S/T)-X(3)-P-(hb)-C-D-X(2)-H, where hb represents a hydrophobic residue; we term this a CCCH-type [2Fe-2S] binding motif. The nine conserved residues in the motif contribute to iron ligation and structure stabilization. UV-visible absorption spectra indicated that mitoNEET can exist in oxidized and reduced states. Our study suggests an electron transfer function for mitoNEET and for other proteins containing the CCCH motif.
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Affiliation(s)
- Jinzhong Lin
- *National Laboratory of Biomacromolecules, Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; and
- National Institute of Biological Sciences, Beijing 102206, China
| | - Tao Zhou
- *National Laboratory of Biomacromolecules, Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; and
| | - Keqiong Ye
- National Institute of Biological Sciences, Beijing 102206, China
- To whom correspondence may be addressed. E-mail: or
| | - Jinfeng Wang
- *National Laboratory of Biomacromolecules, Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; and
- To whom correspondence may be addressed. E-mail: or
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31
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Abstract
The microtubule-targeting agents are one of the most successful classes of cancer therapeutics. All known antimicrotubule drugs bind to microtubules, or to their constituent tubulin heterodimers, and affect microtubule polymerization and dynamics. Recently, PPAR-gamma inhibitors were shown to reduce tubulin levels without affecting the polymerization of tubulin in vitro. This observation suggests the possible development of antimicrotubule drugs that target tubulin itself, rather than the equilibrium between tubulin and microtubules.
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32
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Abstract
This perspective describes the compounds from the endocrine and metabolic area that were discontinued during the calendar year 2005. This is a continuation of a series of perspectives of each of the editorial areas summarized by Expert Opinion on Investigational Drugs. The candidates for this summary were being developed in the areas of treatment of diabetes and diabetes complications, as well as reproductive and urogenital health issues.
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Affiliation(s)
- Jerry R Colca
- Kalamazoo Metabolic Research, 125 South Kalamazoo, Mall number 604, Kalamazoo, MI 49007, USA.
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33
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Abstract
Oral antidiabetic agents were introduced into clinical practice during the 1950s. Biguanides and sulfonylureas are still used extensively today and their safety and tolerability profiles are well defined. Developments and refinements within these classes have included the introduction of second- and third-generation sulfonylureas, the introduction of modified-release preparations, and the emergence of fixed-dose preparations with metformin and with novel drugs. The latter include the thiazolidinediones, agents with a putative genomic mechanism of action that have been under intense scrutiny since the emergence of severe hepatotoxicity with troglitazone. Recent concerns about thiazolidinediones have centred on the issue of oedema and the risk of precipitating heart failure in vulnerable patients. Only prolonged exposure will determine the long-term safety of thiazolidinediones. Rapid-acting non-sulfonylurea secretagogues appear to be effective and perhaps safer than sulfonylureas in some groups of patients with certain comorbidities (e.g., those with renal impairment). alpha-Glucosidase inhibitors have an excellent safety record and acarbose has been shown to retard the progression from impaired glucose tolerance to Type 2 diabetes. However, their use is limited by tolerability issues.
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Affiliation(s)
- Andrew J Krentz
- Consultant in Diabetes & Endocrinology, Southampton University Hospitals NHS Trust, University of Southampton, Southampton SO16 6YD, UK.
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34
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Colca J. 66th Annual Meeting of the American Diabetes Association: 9 - 13 June 2006, Washington DC, USA. Expert Opin Investig Drugs 2006; 15:1119-23. [PMID: 16916278 DOI: 10.1517/13543784.15.9.1119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The 66th annual meeting of the American Diabetes Association was held in Washington, DC and attracted the largest attendance ever for this meeting. This meeting continues to be grow in size and quality as the most useful and successful confluence of scientific, medical, and commercial advances relating to diabetes.
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Affiliation(s)
- Jerry Colca
- Kalamazoo Metabolic Research, 125 South Kalamazoo Mall 640, Kalamazoo, MI 49007, USA.
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