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Li Z, Bai R, Yi J, Zhou H, Xian J, Chen C. Designing Smart Iron Oxide Nanoparticles for MR Imaging of Tumors. CHEMICAL & BIOMEDICAL IMAGING 2023; 1:315-339. [PMID: 37501794 PMCID: PMC10369497 DOI: 10.1021/cbmi.3c00026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/14/2023] [Accepted: 04/21/2023] [Indexed: 07/29/2023]
Abstract
Iron oxide nanoparticles (IONPs) possess unique magnetism and good biocompatibility, and they have been widely applied as contrast agents (CAs) for magnetic resonance imaging (MRI). Traditional CAs typically show a fixed enhanced signal, thus exhibiting the limitations of low sensitivity and a lack of specificity. Nowadays, the progress of stimulus-responsive IONPs allows alteration of the relaxation signal in response to internal stimuli of the tumor, or external stimuli, thus providing an opportunity to overcome those limitations. This review summarizes the current status of smart IONPs as tumor imaging MRI CAs that exhibit responsiveness to endogenous stimuli, such as pH, hypoxia, glutathione, and enzymes, or exogenous stimuli, such as magnets, light, and so on. We discuss the challenges and future opportunities for IONPs as MRI CAs and comprehensively illustrate the applications of these stimuli-responsive IONPs. This review will help provide guidance for designing IONPs as MRI CAs and further promote the reasonable design of magnetic nanoparticles and achieve early and accurate tumor detection.
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Affiliation(s)
- Zhenzhen Li
- CAS
Key Laboratory for Biomedical Effects of Nanoparticles and Nanosafety
& CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- Department
of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Ru Bai
- CAS
Key Laboratory for Biomedical Effects of Nanoparticles and Nanosafety
& CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University
of Chinese Academy of Sciences, Beijing 100049, China
- Research
Unit of Nanoscience and Technology, Chinese
Academy of Medical Sciences, Beijing 100021, China
| | - Jia Yi
- Guangdong
Provincial Development and Reform Commission, Guangzhou 510031, China
| | - Huige Zhou
- CAS
Key Laboratory for Biomedical Effects of Nanoparticles and Nanosafety
& CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University
of Chinese Academy of Sciences, Beijing 100049, China
- Research
Unit of Nanoscience and Technology, Chinese
Academy of Medical Sciences, Beijing 100021, China
| | - Junfang Xian
- Department
of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Chunying Chen
- CAS
Key Laboratory for Biomedical Effects of Nanoparticles and Nanosafety
& CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
- University
of Chinese Academy of Sciences, Beijing 100049, China
- Research
Unit of Nanoscience and Technology, Chinese
Academy of Medical Sciences, Beijing 100021, China
- The
GBA National Institute for Nanotechnology Innovation, Guangzhou 510700, China
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2
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Kontoghiorghes GJ. Differences between the European Union and United States of America in Drug Regulatory Affairs Affect Global Patient Safety Standards and Public Health Awareness: The Case of Deferasirox and Other Iron Chelating Drugs. MEDICINES (BASEL, SWITZERLAND) 2021; 8:medicines8070036. [PMID: 34357152 PMCID: PMC8304852 DOI: 10.3390/medicines8070036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/17/2021] [Accepted: 07/05/2021] [Indexed: 06/13/2023]
Abstract
Regulatory policies on drugs have a major impact on patient safety and survival. Some pharmaceutical companies employ all possible methods to achieve maximum sales in relation to the monopoly of their patented drugs, leading sometimes to irregularities and illegal activities. Misinformation on the orphan drug deferasirox has reached the stage of criminal investigations and fines exceeding USD 100 million. Additional lawsuits of USD 3.5 billion for damages and civil fines were also filed by the FBI of the USA involving deferasirox and mycophenolic acid, which were later settled with an additional fine of USD 390 million. Furthermore, a USD 345 million fine was also settled for bribes and other illegal overseas operations including an EU country. However, no similar fines for illegal practises or regulatory control violations have been issued in the EU. Misconceptions and a lack of clear guidelines for the use of deferasirox in comparison to deferiprone and deferoxamine appear to reduce the effective treatment prospects and to increase the toxicity risks for thalassaemia and other iron loaded patients. Similar issues have been raised for the activities of other pharmaceutical companies promoting the use of new patented versus generic drugs. Treatments for different categories of patients using new patented drugs are mostly market driven with no clear safeguards or guidelines for risk/benefit assessment indications or for individualised effective and safe optimum therapies. There is a need for the establishment of an international organisation, which can monitor and assess the risk/benefit assessment and marketing of drugs in the EU and globally for the benefit of patients. The pivotal role of the regulatory drug authorities and the prescribing physicians for identifying individualised optimum therapies is essential for improving the survival and safety of millions of patients worldwide.
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Affiliation(s)
- George J Kontoghiorghes
- Postgraduate Research Institute of Science, Technology, Environment and Medicine, Limassol 3021, Cyprus
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3
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Hoffmann KM, Goncuian ES, Karimi KL, Amendola CR, Mojab Y, Wood KM, Prussia GA, Nix J, Yamamoto M, Lathan K, Orion IW. Cofactor Complexes of DesD, a Model Enzyme in the Virulence-related NIS Synthetase Family. Biochemistry 2020; 59:3427-3437. [PMID: 32885650 DOI: 10.1021/acs.biochem.9b00899] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The understudied nonribosomal-peptide-synthetase-independent siderophore (NIS) synthetase family has been increasingly associated with virulence in bacterial species due to its key role in the synthesis of hydroxamate and carboxylate "stealth" siderophores. We have identified a model family member, DesD, from Streptomyces coelicolor, to structurally characterize using a combination of a wild-type and a Arg306Gln variant in apo, cofactor product AMP-bound, and cofactor reactant ATP-bound complexes. The kinetics in the family has been limited by solubility and reporter assays, so we have developed a label-free kinetics assay utilizing a single-injection isothermal-titration-calorimetry-based method. We report second-order rate constants that are 50 times higher than the previous estimations for DesD. Our Arg306Gln DesD variant was also tested under identical buffer and substrate conditions, and its undetectable activity was confirmed. These are the first reported structures for DesD, and they describe the critical cofactor coordination. This is also the first label-free assay to unambiguously determine the kinetics for an NIS synthetase.
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Affiliation(s)
- Katherine M Hoffmann
- Department of Chemistry, California Lutheran University, 60 West Olsen Road #3700, Thousand Oaks, California 91360, United States
| | - Eliana S Goncuian
- Department of Chemistry, California Lutheran University, 60 West Olsen Road #3700, Thousand Oaks, California 91360, United States
| | - Kimya L Karimi
- Department of Chemistry, California Lutheran University, 60 West Olsen Road #3700, Thousand Oaks, California 91360, United States
| | - Caroline R Amendola
- Department of Chemistry and Biochemistry, Gonzaga University, 502 East Boone Avenue, Spokane, Washington 99258, United States
| | - Yasi Mojab
- Department of Chemistry, California Lutheran University, 60 West Olsen Road #3700, Thousand Oaks, California 91360, United States
| | - Kaitlin M Wood
- Department of Chemistry and Biochemistry, Gonzaga University, 502 East Boone Avenue, Spokane, Washington 99258, United States
| | - Gregory A Prussia
- Department of Chemistry and Biochemistry, Gonzaga University, 502 East Boone Avenue, Spokane, Washington 99258, United States
| | - Jay Nix
- Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Margaret Yamamoto
- Department of Chemistry and Biochemistry, Gonzaga University, 502 East Boone Avenue, Spokane, Washington 99258, United States
| | - Kiera Lathan
- Department of Chemistry, California Lutheran University, 60 West Olsen Road #3700, Thousand Oaks, California 91360, United States
| | - Iris W Orion
- Department of Chemistry and Biochemistry, Gonzaga University, 502 East Boone Avenue, Spokane, Washington 99258, United States
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4
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Management of Iron Overload in Resource Poor Nations: A Systematic Review of Phlebotomy and Natural Chelators. J Toxicol 2020; 2020:4084538. [PMID: 32399029 PMCID: PMC7204175 DOI: 10.1155/2020/4084538] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/13/2019] [Accepted: 09/20/2019] [Indexed: 12/29/2022] Open
Abstract
Iron is an essential element and the most abundant trace metal in the body involved in oxygen transport and oxygen sensing, electron transfer, energy metabolism, and DNA synthesis. Excess labile and unchelated iron can catalyze the formation of tissue-damaging radicals and induce oxidative stress. English abstracts were identified in PubMed and Google Scholar using multiple and various search terms based on defined inclusion and exclusion criteria. Full-length articles were selected for systematic review, and secondary and tertiary references were developed. Although bloodletting or phlebotomy remains the gold standard in the management of iron overload, this systematic review is an updated account of the pitfalls of phlebotomy and classical synthetic chelators with scientific justification for the use of natural iron chelators of dietary origin in resource-poor nations.
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5
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Wang W, Tabu K, Hagiya Y, Sugiyama Y, Kokubu Y, Murota Y, Ogura SI, Taga T. Enhancement of 5-aminolevulinic acid-based fluorescence detection of side population-defined glioma stem cells by iron chelation. Sci Rep 2017; 7:42070. [PMID: 28169355 PMCID: PMC5294410 DOI: 10.1038/srep42070] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 01/05/2017] [Indexed: 01/20/2023] Open
Abstract
Cancer stem cells (CSCs) are dominantly responsible for tumor progression and chemo/radio-resistance, resulting in tumor recurrence. 5-aminolevulinic acid (ALA) is metabolized to fluorescent protoporphyrin IX (PpIX) specifically in tumor cells, and therefore clinically used as a reagent for photodynamic diagnosis (PDD) and therapy (PDT) of cancers including gliomas. However, it remains to be clarified whether this method could be effective for CSC detection. Here, using flow cytometry-based analysis, we show that side population (SP)-defined C6 glioma CSCs (GSCs) displayed much less 5-ALA-derived PpIX fluorescence than non-GSCs. Among the C6 GSCs, cells with ultralow PpIX fluorescence exhibited dramatically higher tumorigenicity when transplanted into the immune-deficient mouse brain. We further demonstrated that the low PpIX accumulation in the C6 GSCs was enhanced by deferoxamine (DFO)-mediated iron chelation, not by reserpine-mediated inhibition of PpIX-effluxing ABCG2. Finally, we found that the expression level of the gene for heme oxygenase-1 (HO-1), a heme degradation enzyme, was high in C6 GSCs, which was further up-regulated when treated with 5-ALA. Our results provide important new insights into 5-ALA-based PDD of gliomas, particularly photodetection of SP-defined GSCs by iron chelation based on their ALA-PpIX-Heme metabolism.
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Affiliation(s)
- Wenqian Wang
- Department of Stem Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, 1138510, Japan
| | - Kouichi Tabu
- Department of Stem Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, 1138510, Japan
| | - Yuichiro Hagiya
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B102, Nagatsuta-cho, Midori-ku, Yokohama, 2268501, Japan
| | - Yuta Sugiyama
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B102, Nagatsuta-cho, Midori-ku, Yokohama, 2268501, Japan
| | - Yasuhiro Kokubu
- Department of Stem Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, 1138510, Japan
| | - Yoshitaka Murota
- Department of Stem Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, 1138510, Japan
| | - Shun-ichiro Ogura
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B102, Nagatsuta-cho, Midori-ku, Yokohama, 2268501, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 B-47, Nagatsuta-cho, Midori-ku, Yokohama, 2268501, Japan
| | - Tetsuya Taga
- Department of Stem Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, 1138510, Japan
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6
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Murray C, De Gelder T, Pringle N, Johnson JC, Doherty M. Management of iron overload in the Canadian hematology/oncology population: Implications for nursing practice. Can Oncol Nurs J 2016; 26:19-28. [PMID: 31148725 PMCID: PMC6516318 DOI: 10.5737/236880762611928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Red blood cell (RBC) transfusions are vital for many patients with chronic anemias associated with oncologic/hematologic disorders. However, repeated transfusions over time can lead to iron overload, which, if left untreated, can increase the risk of further malignancy and end-organ damage. Nurses and other health care professionals may not be aware of the significant implications of RBC transfusions and iron overload in patients with hematological/oncological disorders. This article was developed by a group of Canadian nurse practitioners and specialized oncology nurses to help improve health care professionals' understanding of iron overload in oncology patients and its associated risks, as well as provide a practical guide for the management of patients receiving treatment for this potentially serious condition.
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Affiliation(s)
- Cindy Murray
- Nurse Practitioner, Blood and Marrow Disorder Program - Transfusion Outpatient Clinic, University Health Network (UHN) Princess Margaret Cancer Centre, Toronto, ON
| | - Tammy De Gelder
- Nurse Practitioner, Hamilton Health Sciences, Juravinski Hospital and Cancer Centre, Hamilton, ON
| | - Nancy Pringle
- Specialized Oncology Nurse, Leukemia Clinic, UHN Princess Margaret Cancer Centre, Toronto, ON
| | - J Colleen Johnson
- Nurse Practitioner, Red Blood Cell Disorders Clinic, UHN, Toronto General Division, Toronto, ON
| | - Mary Doherty
- Nurse Practitioner, Blood and Marrow Disorder Program - Transfusion Outpatient Clinic, University Health Network (UHN) Princess Margaret Cancer Centre, Toronto, ON
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7
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A late presentation of a fatal disease: juvenile hemochromatosis. Case Rep Med 2013; 2013:875093. [PMID: 24106505 PMCID: PMC3784272 DOI: 10.1155/2013/875093] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 08/13/2013] [Indexed: 12/13/2022] Open
Abstract
Juvenile hemochromatosis is a rare and severe form of hereditary hemochromatosis. We report the case of a 39-year-old female who presented with heart failure and cirrhosis from previously unrecognized juvenile hemochromatosis. This is the latest presentation described in the literature. An important clue to the diagnosis was a history of amenorrhea since the age of 20 that had never been investigated. The patient died of intractable heart failure two months after the initial presentation. Juvenile hemochromatosis should be suspected in a young patient with endocrine or cardiac manifestations. Early diagnosis is crucial since phlebotomy can improve the prognosis and delay or prevent progression to heart failure and cirrhosis.
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8
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Dysregulation of iron metabolism in Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Adv Pharmacol Sci 2011; 2011:378278. [PMID: 22013437 PMCID: PMC3195304 DOI: 10.1155/2011/378278] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 07/09/2011] [Accepted: 07/25/2011] [Indexed: 12/22/2022] Open
Abstract
Dysregulation of iron metabolism has been observed in patients with neurodegenerative diseases (NDs). Utilization of several importers and exporters for iron transport in brain cells helps maintain iron homeostasis. Dysregulation of iron homeostasis leads to the production of neurotoxic substances and reactive oxygen species, resulting in iron-induced oxidative stress. In Alzheimer's disease (AD) and Parkinson's disease (PD), circumstantial evidence has shown that dysregulation of brain iron homeostasis leads to abnormal iron accumulation. Several genetic studies have revealed mutations in genes associated with increased iron uptake, increased oxidative stress, and an altered inflammatory response in amyotrophic lateral sclerosis (ALS). Here, we review the recent findings on brain iron metabolism in common NDs, such as AD, PD, and ALS. We also summarize the conventional and novel types of iron chelators, which can successfully decrease excess iron accumulation in brain lesions. For example, iron-chelating drugs have neuroprotective effects, preventing neural apoptosis, and activate cellular protective pathways against oxidative stress. Glial cells also protect neurons by secreting antioxidants and antiapoptotic substances. These new findings of experimental and clinical studies may provide a scientific foundation for advances in drug development for NDs.
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9
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Gujja P, Rosing DR, Tripodi DJ, Shizukuda Y. Iron overload cardiomyopathy: better understanding of an increasing disorder. J Am Coll Cardiol 2010; 56:1001-12. [PMID: 20846597 PMCID: PMC2947953 DOI: 10.1016/j.jacc.2010.03.083] [Citation(s) in RCA: 228] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Revised: 02/26/2010] [Accepted: 03/18/2010] [Indexed: 11/20/2022]
Abstract
The prevalence of iron overload cardiomyopathy (IOC) is increasing. The spectrum of symptoms of IOC is varied. Early in the disease process, patients may be asymptomatic, whereas severely overloaded patients can have terminal heart failure complaints that are refractory to treatment. It has been shown that early recognition and intervention may alter outcomes. Biochemical markers and tissue biopsy, which have traditionally been used to diagnose and guide therapy, are not sensitive enough to detect early cardiac iron deposition. Newer diagnostic modalities such as magnetic resonance imaging are noninvasive and can assess quantitative cardiac iron load. Phlebotomy and chelating drugs are suboptimal means of treating IOC; hence, the roles of gene therapy, hepcidin, and calcium channel blockers are being actively investigated. There is a need for the development of clinical guidelines in order to improve the management of this emerging complex disease.
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Affiliation(s)
- Pradeep Gujja
- Division of Cardiovascular Diseases, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio 45267-0542, USA.
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10
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Chu BC, Garcia-Herrero A, Johanson TH, Krewulak KD, Lau CK, Peacock RS, Slavinskaya Z, Vogel HJ. Siderophore uptake in bacteria and the battle for iron with the host; a bird’s eye view. Biometals 2010; 23:601-11. [DOI: 10.1007/s10534-010-9361-x] [Citation(s) in RCA: 236] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 06/16/2010] [Indexed: 02/07/2023]
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11
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Lim J, Venditto VJ, Simanek EE. Synthesis and characterization of a triazine dendrimer that sequesters iron(III) using 12 desferrioxamine B groups. Bioorg Med Chem 2010; 18:5749-53. [PMID: 20615715 DOI: 10.1016/j.bmc.2010.05.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 05/12/2010] [Accepted: 05/14/2010] [Indexed: 01/19/2023]
Abstract
The synthesis of a third generation triazine dendrimer, 1, containing multiple, iron-sequestering desferrioxamine B (DFO) groups is described. Benzoylation of the hydroxamic acid groups of DFO and formation of a reactive dichlorotriazine provide the intermediate for reaction with the second generation dendrimer displaying twelve amines. This strategy further generalizes the 'functional monomer' approach to generate biologically active triazine dendrimers. Dendrimer 1 is prepared in seven steps in 35% overall yield and displays 12 DFO groups making it 56% drug by weight. Spectrophotometric titrations (UV-vis) show that 1 sequesters iron(III) atoms with neither cooperativity nor significant interference from the dendrimer backbone. Evidence from NMR spectroscopy and mass spectrometry reveals a limitation to this functional monomer approach: trace amounts of O-to-N acyl migration from the protected hydroxamic acids to the amine-terminated dendrimer occurs during the coupling step leading to N-benzoylated dendrimers displaying fewer than 12 DFO groups.
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Affiliation(s)
- Jongdoo Lim
- Department of Chemistry, Texas A&M University, College Station, TX 77843, United States
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12
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Valdés PA, Samkoe K, O'Hara JA, Roberts DW, Paulsen KD, Pogue BW. Deferoxamine iron chelation increases delta-aminolevulinic acid induced protoporphyrin IX in xenograft glioma model. Photochem Photobiol 2009; 86:471-5. [PMID: 20003159 DOI: 10.1111/j.1751-1097.2009.00664.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Exogenous administration of delta-aminolevulinic acid (delta-ALA) leads to selective accumulation of protoporphyrin IX (PpIX) in brain tumors, and has shown promising results in increasing extent of resection in fluorescence-guided resection (FGR) of brain tumors. However, this approach still suffers from heterogeneous staining and so some tumor margins may go undetected because of this variation in PpIX production. The aim of this study was to test the hypothesis that iron chelation therapy could increase the level of fluorescence in malignant glioma tumors. Mice implanted with xenograft U251-GFP glioma tumor cells were given a 200 mg kg(-1) dose of deferoxamine (DFO), once a day for 3 days prior to delta-ALA administration. The PpIX fluorescence observed in the tumor regions was 1.9 times the background in animal group without DFO, and 2.9 times the background on average, in the DFO pre-treated group. A 50% increase in PpIX fluorescence contrast in the DFO group was observed relative to the control group (t-test P-value = 0.0020). These results indicate that iron chelation therapy could significantly increase delta-ALA-induced PpIX fluorescence in malignant gliomas, pointing to a potential role of iron chelation therapy for more effective FGR of brain tumors.
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Affiliation(s)
- Pablo A Valdés
- Dartmouth Medical School, Dartmouth College, Hanover, NH, USA.
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13
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Abstract
Although chronic infection with hepatitis B virus and/or hepatitis C virus are the most important risk factors for hepatocellular carcinoma (HCC) worldwide, other causes of cirrhosis can also lead to HCC. Given the high prevalence of alcoholism and the worldwide obesity epidemic, the relevant importance of nonviral liver disease-related HCC is expected to increase in the future. Some evidence supports mechanistic interactions between host or environmental factors and chronic viral hepatitis in the development of HCC. For example, food- and water-borne carcinogens have contributed to unusually high rates of HCC in parts of China and sub-Saharan Africa. With some of these conditions, appropriate public health measures to reduce the population's exposure to known etiologic agents, or early therapeutic intervention for 'at-risk' individuals before development of cirrhosis (e.g. hereditary hemochromatosis) can prevent HCC. Community-based programs to discourage and deal with excessive alcohol intake, to promote tobacco smoking awareness, to avoid exposure to aflatoxin and other food toxins, and measures to reduce the pandemic of obesity and diabetes are vital for effective interruption of the rising tide of HCC from nonviral liver disease.
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Affiliation(s)
- Jian-Gao Fan
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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14
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Abstract
Haemochromatosis should currently refer to hereditary iron overload disorders presenting with a definite and common phenotype characterised by normal erythropoiesis, increased transferrin saturation and ferritin and primarily parenchymal iron deposition related to innate low (but normally regulated) production of the hepatic peptide hormone hepcidin. Since the discovery of the haemochromatosis gene (HFE) in 1996, several novel gene defects have been detected, explaining the mechanism and diversity of iron overload diseases. Overall, at least four main types of hereditary haemochromatosis (HH) have been identified. This review describes the systematic diagnostic and therapeutic strategy and pitfalls for patients suspected for HH and their relatives.
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Affiliation(s)
- M C H Janssen
- Radboud University Medical Centre, Department of General Internal Medicine 463, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
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15
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Bommer M, Heimpel H. [Iron metabolism disorders]. PHARMAZIE IN UNSERER ZEIT 2009; 38:242-250. [PMID: 19396907 DOI: 10.1002/pauz.200800314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Affiliation(s)
- Martin Bommer
- Medizinische Universitätsklinik, Albert-Einstein-Allee 23, 89081 Ulm.
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