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Brisdelli F, Bognanni N, Piccirilli A, Perilli M, Bellotti D, Remelli M, Vecchio G. Polyimidazole ligands: Copper(II) complexes and antiproliferative activity in cancer cells. J Inorg Biochem 2024; 260:112685. [PMID: 39142054 DOI: 10.1016/j.jinorgbio.2024.112685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 07/11/2024] [Accepted: 07/29/2024] [Indexed: 08/16/2024]
Abstract
The design of novel chelators for therapeutic applications has been the subject of extensive research to address various diseases. Many chelators can manipulate the levels of metal ions within cells and effectively modulate the metal excess. In some cases, chelators show significant toxicity to cells. We investigated polyimidazole ligands by potentiometry and UV-Vis spectroscopy for their ability to form copper(II) complexes. We also compared the antiproliferative activity of the polyimidazole ligands and their copper(II) complexes with polypyridine ligands in CaCo-2 (colorectal adenocarcinoma), SH-SY5Y (neuroblastoma) and K562 (chronic myelogenous leukemia) cells and normal HaCaT (keratinocyte) cells. Polyimidazole ligands are less cytotoxic than their analogous polypyridine ligands. All polyimidazole ligands, except the tetraimidazole ligand for K562 cells, did not show any significant effect on the viability of cancer and normal cells. In contrast, the cytotoxic activity of polypiridine ligands was also observed in normal cells with IC50 values similar to those of cancer cells. Tetraimidazole ligand, the only ligand active on the leukemic K562 cell line, induced caspase-dependent apoptosis and increased intracellular reactive oxygen species production with mitochondrial damage. The low cytotoxicity of the polyimidazole ligands, even if it limits their use as anticancer agents, could make them useful in other medical applications, such as in the treatment of metal overload, microbial infections, inflammation or neurodegenerative disorders.
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Affiliation(s)
- Fabrizia Brisdelli
- Dipartimento di Scienze Cliniche Applicate e Biotecnologiche, Università degli Studi dell'Aquila, via Vetoio, Coppito 67100, L'Aquila, Italy
| | - Noemi Bognanni
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A. Doria 6, 95125 Catania, Italy
| | - Alessandra Piccirilli
- Dipartimento di Scienze Cliniche Applicate e Biotecnologiche, Università degli Studi dell'Aquila, via Vetoio, Coppito 67100, L'Aquila, Italy
| | - Mariagrazia Perilli
- Dipartimento di Scienze Cliniche Applicate e Biotecnologiche, Università degli Studi dell'Aquila, via Vetoio, Coppito 67100, L'Aquila, Italy
| | - Denise Bellotti
- Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Università degli Studi di Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Maurizio Remelli
- Dipartimento di Scienze Chimiche, Farmaceutiche ed Agrarie, Università degli Studi di Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Graziella Vecchio
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A. Doria 6, 95125 Catania, Italy.
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Hamu-Tanoue A, Takagi K, Taketomi Y, Miki Y, Nishito Y, Kano K, Aoki J, Matsuyama T, Kondo K, Dotake Y, Matsuyama H, Machida K, Murakami M, Inoue H. Group III secreted phospholipase A 2 -driven lysophospholipid pathway protects against allergic asthma. FASEB J 2024; 38:e23428. [PMID: 38236184 DOI: 10.1096/fj.202301976r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/21/2023] [Accepted: 01/03/2024] [Indexed: 01/19/2024]
Abstract
Asthma is a chronic inflammatory disease of the airways characterized by recurrent episodes of airway obstruction, hyperresponsiveness, remodeling, and eosinophilia. Phospholipase A2 s (PLA2 s), which release fatty acids and lysophospholipids from membrane phospholipids, have been implicated in exacerbating asthma by generating pro-asthmatic lipid mediators, but an understanding of the association between individual PLA2 subtypes and asthma is still incomplete. Here, we show that group III-secreted PLA2 (sPLA2 -III) plays an ameliorating, rather than aggravating, role in asthma pathology. In both mouse and human lungs, sPLA2 -III was expressed in bronchial epithelial cells and decreased during the asthmatic response. In an ovalbumin (OVA)-induced asthma model, Pla2g3-/- mice exhibited enhanced airway hyperresponsiveness, eosinophilia, OVA-specific IgE production, and type 2 cytokine expression as compared to Pla2g3+/+ mice. Lipidomics analysis showed that the pulmonary levels of several lysophospholipids, including lysophosphatidylcholine, lysophosphatidylethanolamine, and lysophosphatidic acid (LPA), were decreased in OVA-challenged Pla2g3-/- mice relative to Pla2g3+/+ mice. LPA receptor 2 (LPA2 ) agonists suppressed thymic stromal lymphopoietin (TSLP) expression in bronchial epithelial cells and reversed airway hyperresponsiveness and eosinophilia in Pla2g3-/- mice, suggesting that sPLA2 -III negatively regulates allergen-induced asthma at least by producing LPA. Thus, the activation of the sPLA2 -III-LPA pathway may be a new therapeutic target for allergic asthma.
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Affiliation(s)
- Asako Hamu-Tanoue
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Koichi Takagi
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Yoshitaka Taketomi
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yoshimi Miki
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yasumasa Nishito
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Kuniyuki Kano
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Takahiro Matsuyama
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Kiyotaka Kondo
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Yoichi Dotake
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Hiromi Matsuyama
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Kentaro Machida
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Science, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- AMED-CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
| | - Hiromasa Inoue
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
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Incense smoke-induced oxidative stress disrupts tight junctions and bronchial epithelial barrier integrity and induces airway hyperresponsiveness in mouse lungs. Sci Rep 2021; 11:7222. [PMID: 33790367 PMCID: PMC8012366 DOI: 10.1038/s41598-021-86745-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/19/2021] [Indexed: 12/01/2022] Open
Abstract
Recent clinical studies have suggested that inhalation of incense smoke (IS) may result in impaired lung function and asthma. However, there is little experimental evidence to link IS with airway hyperresponsiveness (AHR) and bronchial epithelial barrier function. Using mouse and cell culture models, we evaluated the effects of IS exposure on AHR, expression of multiple epithelial tight junction (TJ)- and adherens junction-associated mRNAs and proteins in the lungs, and the barrier function of bronchial epithelial cells assessed by transepithelial electronic resistance (TEER). Exposure of BALB/c mice to IS increased AHR and inflammatory macrophage recruitment to BALF; reduced claudin-1, -2, -3, -7, -10b, -12, -15, and -18, occludin, zonula occludens-1 [ZO-1], and E-cadherin mRNA expression; and caused discontinuity of claudin-2 and ZO-1 protein immunostaining in lung tissue. IS extract dose-dependently decreased TEER and increased reactive oxygen species production in bronchial epithelial cell cultures. Treatment with N-acetyl-l-cysteine, but not glucocorticosteroids or long-acting β2-agonists, prevented the detrimental effects of IS. IS exposure can be problematic for respiratory health, as evidenced by AHR, increased recruitment of inflammatory macrophages and disruption of TJ proteins in the lung, and damage to epithelial barrier function. However, antioxidants may be useful for the treatment of IS-induced airway dysfunction.
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Wessels I, Fischer HJ, Rink L. Update on the multi-layered levels of zinc-mediated immune regulation. Semin Cell Dev Biol 2020; 115:62-69. [PMID: 33323322 DOI: 10.1016/j.semcdb.2020.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/10/2020] [Accepted: 11/10/2020] [Indexed: 11/15/2022]
Abstract
The significance of zinc for an efficient immune response is well accepted. During zinc deficiency, an increase in the myeloid to lymphoid immune cells ratio was observed. This results in a disturbed balance of pro- and anti-inflammatory processes as well as defects in tolerance during infections. Consequently, instead of efficiently defending the body against invading pathogens, damage of host cells is frequently observed. This explains the increased susceptibility to infections and their severe progression observed for zinc deficient individuals as well as the association of autoimmune diseases with low serum zinc levels. Together with the advances in techniques for investigating cellular development, communication and intracellular metabolism, our understanding of the mechanisms underlying the benefits of zinc for human health and the detriments of zinc deficiency has much improved. As analyses of the zinc status and effects of zinc supplementation were more frequently included into clinical studies, our knowledge of the association of zinc deficiency to a variety of diseases was strongly improved. Still there are several areas in zinc biology that require further in-depth investigation such as the interaction with other nutritional elements, the direct association between zinc transportation, membrane-structure, receptors, and signaling as well as its role in cell degeneration. This article will describe our current understanding of the role of zinc during the immune response focusing on the most recent findings and underlying mechanisms. Research questions that need to be addressed in the future will be discussed as well.
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Affiliation(s)
- Inga Wessels
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
| | - Henrike J Fischer
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
| | - Lothar Rink
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
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La Piana L, Viaggi V, Principe L, Di Bella S, Luzzaro F, Viale M, Bertola N, Vecchio G. Polypyridine ligands as potential metallo-β-lactamase inhibitors. J Inorg Biochem 2020; 215:111315. [PMID: 33285370 DOI: 10.1016/j.jinorgbio.2020.111315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 11/19/2022]
Abstract
Bacteria have developed multiple resistance mechanisms against the most used antibiotics. In particular, zinc-dependent metallo-β-lactamase producing bacteria are a growing threat, and therapeutic options are limited. Zinc chelators have recently been investigated as metallo-β-lactamase inhibitors, as they are often able to restore carbapenem susceptibility. We synthesized polypyridyl ligands, N,N'-bis(2-pyridylmethyl)-ethylenediamine, N,N,N'-tris(2-pyridylmethyl)-ethylenediamine, N,N'-bis(2-pyridylmethyl)-ethylenediamine-N-acetic acid (N,N,N'-tris(2-pyridylmethyl)-ethylenediamine-N'-acetic acid, which can form zinc(II) complexes. We tested their ability to restore the antibiotic activity of meropenem against three clinical strains isolated from blood and metallo-β-lactamase producers (Klebsiella pneumoniae, Enterobacter cloacae, and Stenotrophomonas maltophilia). We functionalized N,N,N'-tris(2-pyridylmethyl)-ethylenediamine with D-alanyl-D-alanyl-D-alanine methyl ester with the aim to increase bacterial uptake. We observed synergistic activity of four polypyridyl ligands with meropenem against all tested isolates, while the combination N,N'-bis(2-pyridylmethyl)-ethylenediamine and meropenem was synergistic only against New Delhi and Verona integron-encoded metallo-β-lactamase-producing bacteria. All synergistic interactions restored the antimicrobial activity of meropenem, providing a significant decrease of minimal inhibitory concentration value (by 8- to 128-fold). We also studied toxicity of the ligands in two normal peripheral blood lymphocytes.
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Affiliation(s)
- Luana La Piana
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A. Doria 6, 95125 Catania, Italy
| | - Valentina Viaggi
- Clinical Microbiology and Virology Unit, A. Manzoni Hospital, Via dell'Eremo 9/11, 23900 Lecco, Italy
| | - Luigi Principe
- Clinical Pathology and Microbiology Unit, San Giovanni di Dio Hospital, Largo Bologna, 88900 Crotone, Italy
| | - Stefano Di Bella
- Clinical Department of Medical, Surgical and Health Sciences, Trieste University, strada di Fiume 447, 34149 Trieste, Italy
| | - Francesco Luzzaro
- Clinical Microbiology and Virology Unit, A. Manzoni Hospital, Via dell'Eremo 9/11, 23900 Lecco, Italy
| | - Maurizio Viale
- IRCCS Ospedale Policlinico San Martino, U.O. Bioterapie, L.go R. Benzi 10, 16132 Genova, Italy
| | - Nadia Bertola
- IRCCS Ospedale Policlinico San Martino, U.O. Bioterapie, L.go R. Benzi 10, 16132 Genova, Italy
| | - Graziella Vecchio
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A. Doria 6, 95125 Catania, Italy; Consorzio Interuniversitario di Ricerca in Chimica dei Metalli nei Sistemi Biologici (CIRCMSB), Piazza Umberto I 1, 70121 Bari, Italy.
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Fujita A, Kan-O K, Tonai K, Yamamoto N, Ogawa T, Fukuyama S, Nakanishi Y, Matsumoto K. Inhibition of PI3Kδ Enhances Poly I:C-Induced Antiviral Responses and Inhibits Replication of Human Metapneumovirus in Murine Lungs and Human Bronchial Epithelial Cells. Front Immunol 2020; 11:432. [PMID: 32218789 PMCID: PMC7079687 DOI: 10.3389/fimmu.2020.00432] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/25/2020] [Indexed: 12/20/2022] Open
Abstract
Viral infections of the airway can exacerbate respiratory diseases, such as asthma or chronic obstructive pulmonary disease (COPD), and accelerate disease progression. Phosphoinositide 3-kinase (PI3K)δ, a class 1A PI3K, has been studied as a potential target for achieving anti-oncogenic and anti-inflammatory effects. However, the role of PI3Kδ in antiviral responses is poorly understood. Using a synthetic double-stranded RNA poly I:C and a selective PI3Kδ inhibitor IC87114, we investigated the role of PI3Kδ signaling in poly I:C-induced expression of the T lymphocyte-inhibitory molecule programmed death 1 ligand 1 (PD-L1), inflammatory responses and antiviral interferon (IFN) responses. C57BL/6N mice were treated with IC87114 or vehicle by intratracheal (i.t.) instillation followed by i.t. administration of poly I:C. Poly I:C increased PD-L1 expression on epithelial cells, lymphocytes, macrophages, and neutrophils in the lungs and IC87114 suppressed poly I:C-induced PD-L1 expression on epithelial cells and neutrophils possibly via inhibition of the Akt/mTOR signaling pathway. IC87114 also attenuated poly I:C-induced increases in numbers of total cells, macrophages, neutrophils and lymphocytes, as well as levels of KC, IL-6 and MIP-1β in bronchoalveolar lavage fluid. Gene expression of IFNβ, IFNλ2 and IFN-stimulated genes (ISGs) were upregulated in response to poly I:C and a further increase in gene expression was observed following IC87114 treatment. In addition, IC87114 enhanced poly I:C-induced phosphorylation of IRF3. We assessed the effects of IC87114 on human primary bronchial epithelial cells (PBECs). IC87114 decreased poly I:C-induced PD-L1 expression on PBECs and secretion of IL-6 and IL-8 into culture supernatants. IC87114 further enhanced poly I:C- induced increases in the concentrations of IFNβ and IFNλ1/3 in culture supernatants as well as upregulated gene expression of ISGs in PBECs. Similar results were obtained in PBECs transfected with siRNA targeting the PIK3CD gene encoding PI3K p110δ, and stimulated with poly I:C. In human metapneumovirus (hMPV) infection of PBECs, IC87114 suppressed hMPV-induced PD-L1 expression and reduced viral replication without changing the production levels of IFNβ and IFNλ1/3 in culture supernatants. These data suggest that IC87114 may promote virus elimination and clearance through PD-L1 downregulation and enhanced antiviral IFN responses, preventing prolonged lung inflammation, which exacerbates asthma and COPD.
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Affiliation(s)
- Akitaka Fujita
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Keiko Kan-O
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Endoscopic Diagnostics and Therapeutics, Kyushu University Hospital, Fukuoka, Japan
| | - Ken Tonai
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Division of Intensive Care, Department of Anesthesiology and Intensive Care Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Norio Yamamoto
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Tomohiro Ogawa
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Satoru Fukuyama
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yoichi Nakanishi
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Koichiro Matsumoto
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Kimura H, Yoneya Y, Mikawa S, Kaji N, Ito H, Tsuchida Y, Komatsu H, Murata T, Ozaki H, Uchida R, Nishida K, Hori M. A new zinc chelator, IPZ-010 ameliorates postoperative ileus. Biomed Pharmacother 2019; 123:109773. [PMID: 31862476 DOI: 10.1016/j.biopha.2019.109773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/29/2019] [Accepted: 12/04/2019] [Indexed: 12/26/2022] Open
Abstract
Zinc was discovered to be a novel second messenger in immunoreactive cells. We synthesized a novel free zinc chelator, IPZ-010. Here, we investigated the effects of IPZ-010 in a mouse postoperative ileus model and determined the effects of zinc signal inhibition as a new therapeutic strategy against postoperative ileus. Zinc waves were measured in bone marrow-derived mast cells (BMMCs) loaded with a zinc indicator, Newport green. Degranulation and cytokine expression were measured in BMMCs and bone marrow-derived macrophages (BMDMs). Postoperative ileus model mice were established with intestinal manipulation. Mice were treated with IPZ-010 (30 mg/kg, s.c. or p.o.) 1 h before and 2 h and 4 h after intestinal manipulation. Gastrointestinal transit, inflammatory cell infiltration, and expression of inflammatory mediators were measured. Free zinc waves occurred following antigen stimulation in BMMCs and were blocked by IPZ-010. IPZ-010 inhibited interleukin-6 secretion and degranulation in BMMCs. IPZ-010 inhibited tumor necrosis factor-α mRNA expression in BMMCs stimulated with lipopolysaccharide or adenosine triphosphate, whereas IPZ-010 had no effects on tumor necrosis factor-α mRNA expression in BMDMs stimulated with lipopolysaccharide or adenosine triphosphate. In postoperative ileus model mice, IPZ-010 inhibited leukocyte infiltration and cytokine expression, which ameliorated gastrointestinal transit. Furthermore, ketotifen (1 mg/kg) induced similar effects as IPZ-010. These effects were not amplified by co-administration of IPZ-010 and ketotifen. IPZ-010 inhibited zinc waves, resulting in inhibition of inflammatory responses in activated BMMCs in vitro. Targeting zinc waves in inflammatory cells may be a novel therapeutic strategy for treating postoperative ileus.
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Affiliation(s)
- Hitomi Kimura
- Department of Veterinary Pharmacology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yutaka Yoneya
- Department of Veterinary Pharmacology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shoma Mikawa
- Department of Veterinary Pharmacology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Noriyuki Kaji
- Department of Veterinary Pharmacology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroki Ito
- Interprotein Corporation, 3-10-2 Toyosaki, Kita-ku, Osaka-city, Osaka 531-0072, Japan
| | - Yasuaki Tsuchida
- Department of Surgical Pathology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya-city, Hyogo 663-8501, Japan
| | - Hirotsugu Komatsu
- Interprotein Corporation, 3-10-2 Toyosaki, Kita-ku, Osaka-city, Osaka 531-0072, Japan
| | - Takahisa Murata
- Department of Animal Radiology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroshi Ozaki
- Department of Veterinary Pharmacology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Ryota Uchida
- Laboratory of Immune Regulation, Graduate School of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3 Minamitamagaki-cho, Suzuka-city, Mie 513-8607, Japan
| | - Keigo Nishida
- Laboratory for Homeostatic Network, RCAI, RIKEN Research Center for Integrative Medical Sciences (IMS-RCAI), 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama-city, Kanagawa 230-0045, Japan; Laboratory of Immune Regulation, Graduate School of Pharmaceutical Sciences, Suzuka University of Medical Science, 3500-3 Minamitamagaki-cho, Suzuka-city, Mie 513-8607, Japan
| | - Masatoshi Hori
- Department of Veterinary Pharmacology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Soto-Mercado V, Mendivil-Perez M, Urueña-Pinzon C, Fiorentino S, Velez-Pardo C, Jimenez-Del-Rio M. TPEN Exerts Antitumor Efficacy in Murine Mammary Adenocarcinoma Through an H2O2 Signaling Mechanism Dependent on Caspase-3. Anticancer Agents Med Chem 2019; 18:1617-1628. [PMID: 29697031 DOI: 10.2174/1871520618666180426111520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/17/2018] [Accepted: 04/23/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND Breast cancer is the second most common cancer worldwide. N, N, N', N'-Tetrakis (2-pyridylmethyl)-ethylenediamine (TPEN) is a lipid-soluble zinc metal chelator that induces apoptosis in cancer cells through oxidative stress (OS). However, the effectiveness and the mechanisms involved in TPENinduced cell death in mammary adenocarcinoma cells in vitro and in vivo are still unclear. OBJECTIVE This study aimed to evaluate the cytotoxic effect of TPEN in mouse embryonic fibroblasts (MEFs, as normal control cells) and mammary adenocarcinoma cancer cells (TS/A cells) in vitro and in a mammary tumor model in vivo. METHODS Cells were treated with TPEN (0-3 µM), and changes in nuclear chromatin and DNA, mitochondrial membrane potential (ΔΨm), and intracellular reactive oxygen species (ROS) levels were determined by both fluorescence microscopy and flow cytometry. Cell proliferation and the cell cycle were also analyzed. Cellular markers of apoptosis were evaluated by Western blot. Finally, the effect of TPEN in a mammary adenocarcinoma tumor model in vivo was determined by immunohistological analyses. RESULTS TPEN induced apoptosis in TS/A cells in a dose-dependent manner, increasing nuclear chromatin condensation, DNA fragmentation, cell cycle arrest and ΔΨm loss. Additionally, TPEN increased dichlorofluorescein fluorescence (DCF+) intensity, indicative of ROS production; increased DJ-1-Cys106-sulfonate expression, a marker of intracellular H2O2 stress; induced p53 and PUMA upregulation; and activated caspase-3. Moreover, TPEN induced mammary cancer cell elimination and tumor size reduction in vivo 48 h after treatment through an OS-induced apoptotic mechanism. CONCLUSION TPEN selectively induces apoptosis in TS/A cells through an H2O2-mediated signaling pathway. Our findings support the use of TPEN as a potential treatment for breast cancer.
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Affiliation(s)
- Viviana Soto-Mercado
- Neuroscience Research Group, Medical Research Institute, Faculty of Medicine, University of Antioquia (UdeA), Calle 70 No. 52-21, and Calle 62 # 52-59, Building 1, Room 412; SIU Medellin, Colombia
| | - Miguel Mendivil-Perez
- Neuroscience Research Group, Medical Research Institute, Faculty of Medicine, University of Antioquia (UdeA), Calle 70 No. 52-21, and Calle 62 # 52-59, Building 1, Room 412; SIU Medellin, Colombia
| | - Claudia Urueña-Pinzon
- Grupo de Inmunobiologia y Biologia Celular, Facultad de Ciencias, Departamento de Microbiología, Pontificia Universidad Javeriana, Carrera 7 No. 40 - 62, Bogota, Colombia
| | - Susana Fiorentino
- Grupo de Inmunobiologia y Biologia Celular, Facultad de Ciencias, Departamento de Microbiología, Pontificia Universidad Javeriana, Carrera 7 No. 40 - 62, Bogota, Colombia
| | - Carlos Velez-Pardo
- Neuroscience Research Group, Medical Research Institute, Faculty of Medicine, University of Antioquia (UdeA), Calle 70 No. 52-21, and Calle 62 # 52-59, Building 1, Room 412; SIU Medellin, Colombia
| | - Marlene Jimenez-Del-Rio
- Neuroscience Research Group, Medical Research Institute, Faculty of Medicine, University of Antioquia (UdeA), Calle 70 No. 52-21, and Calle 62 # 52-59, Building 1, Room 412; SIU Medellin, Colombia
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9
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Tamura K, Matsumoto K, Fukuyama S, Kan-O K, Ishii Y, Tonai K, Tatsuta M, Enokizu A, Inoue H, Nakanishi Y. Frequency-dependent airway hyperresponsiveness in a mouse model of emphysema and allergic inflammation. Physiol Rep 2019; 6. [PMID: 29368450 PMCID: PMC5789724 DOI: 10.14814/phy2.13568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/08/2017] [Accepted: 12/12/2017] [Indexed: 11/24/2022] Open
Abstract
Asthma and chronic obstructive pulmonary disease (COPD), chronic airway inflammatory diseases characterized by airflow limitation, have different etiologies and pathophysiologies. Asthma–COPD Overlap (ACO) has recently been used for patients with mixed asthma and COPD. The pathophysiological mechanisms of ACO have not been clearly understood due to the lack of an appropriate murine model. To investigate its pathophysiology, we examined a murine model by allergen challenge in surfactant protein‐D (SP‐D)‐deficient mice that spontaneously developed pulmonary emphysema. SP‐D‐deficient mice were sensitized and challenged by ovalbumin (OVA). Lungs and bronchoalveolar lavage fluid (BALF) were collected for analysis, and static lung compliance and airway hyperresponsiveness (AHR) were measured 48 h after the last OVA challenge. In SP‐D‐deficient, naïve, or OVA‐challenged mice, the mean linear intercept and static lung compliance were increased compared with wild‐type (WT) mice. There was no significant difference in goblet cell hyperplasia and the gene expression of Mucin 5AC (MUC5AC) between SP‐D‐deficient and WT OVA‐challenged mice. In SP‐D‐deficient OVA‐challenged mice, airway hyperresponsiveness was significantly enhanced despite the lower eosinophil count and the concentration of interleukin (IL)‐5 and IL‐13 in BALF compared with WT OVA‐challenged mice at 120 ventilations per minute. When mice were ventilated at a lower ventilation frequency of 100 ventilations per minute, elevated airway hyperresponsiveness in SP‐D‐deficient OVA‐challenged mice was diminished. This model of emphysematous change with allergic airway inflammation raises the possibility that frequency‐dependent airway hyperresponsiveness may be involved in the pathophysiology of ACO.
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Affiliation(s)
- Kentaro Tamura
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Koichiro Matsumoto
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Satoru Fukuyama
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Keiko Kan-O
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yumiko Ishii
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Ken Tonai
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Miyoko Tatsuta
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Aimi Enokizu
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiromasa Inoue
- Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Yoichi Nakanishi
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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10
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Role of Zinc Signaling in the Regulation of Mast Cell-, Basophil-, and T Cell-Mediated Allergic Responses. J Immunol Res 2018; 2018:5749120. [PMID: 30596108 PMCID: PMC6286780 DOI: 10.1155/2018/5749120] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 10/23/2018] [Indexed: 01/26/2023] Open
Abstract
Zinc is essential for maintaining normal structure and physiological function of cells. Its deficiency causes growth retardation, immunodeficiency, and neuronal degeneration. Zinc homeostasis is tightly regulated by zinc transporters and metallothioneins that control zinc concentration and its distribution in individual cells and contributes to zinc signaling. The intracellular zinc signaling regulates immune reactions. Although many molecules involved in these processes have zinc-binding motifs, the molecular mechanisms and the role of zinc in immune responses have not been elucidated. We and others have demonstrated that zinc signaling plays diverse and specific roles in vivo and in vitro in studies using knockout mice lacking zinc transporter function and metallothionein function. In this review, we discuss the impact of zinc signaling focusing particularly on mast cell-, basophil-, and T cell-mediated inflammatory and allergic responses. We also describe zinc signaling dysregulation as a leading health problem in inflammatory disease and allergy.
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11
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Chen TI, Chen MYC. Zinc Is Indispensable in Exercise-Induced Cardioprotection against Intermittent Hypoxia-Induced Left Ventricular Function Impairment in Rats. PLoS One 2016; 11:e0168600. [PMID: 27977796 PMCID: PMC5158066 DOI: 10.1371/journal.pone.0168600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 12/03/2016] [Indexed: 01/19/2023] Open
Abstract
In obstructive sleep apnea (OSA), recurrent obstruction of the upper airway leads to intermittent hypoxia (IH) during sleep, which can result in impairment of cardiac function. Although exercise can have beneficial effects against IH-induced cardiac dysfunction, the mechanism remains unclear. This study aimed to investigate the interactions of zinc and exercise on IH-triggered left ventricular dysfunction in a rat model that mimics IH in OSA patients. Nine-week-old male Sprague-Dawley rats were randomly assigned to either a control group (CON) or to a group receiving 10 weeks of exercise training (EXE). During weeks 9 and 10, half the rats in each group were subjected to IH for 8 h per day for 14 days (IHCON, IHEXE), whereas the remainder continued to breathe room air. Rats within each of the CON, IHCON, EXE, and IHEXE groups were further randomly assigned to receive intraperitoneal injections of either zinc chloride, the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN), or injection vehicle only. IH induced a lower left ventricular fractional shortening, reduced ejection fraction, higher myocardial levels of inflammatory factors, increased levels oxidative stress, and lower levels of antioxidative capacity, all of which were abolished by zinc treatment. IHEXE rats exhibited higher levels of cardiac function and antioxidant capacity and lower levels of inflammatory factors and oxidative stress than IHCON rats; however, IHEXE rats receiving TPEN did not exhibit these better outcomes. In conclusion, zinc is required for protecting against IH-induced LV functional impairment and likely plays a critical role in exercise-induced cardioprotection by exerting a dual antioxidant and anti-inflammatory effect.
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Affiliation(s)
- Tsung-I Chen
- Center of Physical Education, Office of General and Basic Education, Tzu Chi University, Hualien, Taiwan
- * E-mail:
| | - Michael Yu-Chih Chen
- Department of Cardiology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
- PhD Program in Institute of Medicine, Tzu Chi University, Hualien, Taiwan
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12
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Azumah R, Dutta J, Somboro A, Ramtahal M, Chonco L, Parboosing R, Bester L, Kruger H, Naicker T, Essack S, Govender T. In vitro
evaluation of metal chelators as potential metallo- β -lactamase inhibitors. J Appl Microbiol 2016; 120:860-7. [DOI: 10.1111/jam.13085] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 01/15/2016] [Accepted: 01/26/2016] [Indexed: 01/16/2023]
Affiliation(s)
- R. Azumah
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
- Antimicrobial Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - J. Dutta
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - A.M. Somboro
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
- Antimicrobial Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - M. Ramtahal
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
- Antimicrobial Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - L. Chonco
- Department of Virology; National Health Laboratory Service; University of KwaZulu-Natal; Durban South Africa
| | - R. Parboosing
- Department of Virology; National Health Laboratory Service; University of KwaZulu-Natal; Durban South Africa
| | - L.A. Bester
- Biomedical Resource Unit; University of Kwa-Zulu Natal; Durban South Africa
| | - H.G. Kruger
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - T. Naicker
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - S.Y. Essack
- Antimicrobial Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
| | - T. Govender
- Catalysis and Peptide Research Unit; School of Health Sciences; University of Kwa-Zulu Natal; Durban South Africa
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13
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Curcumin inhibits the increase of labile zinc and the expression of inflammatory cytokines after traumatic spinal cord injury in rats. J Surg Res 2014; 187:646-52. [DOI: 10.1016/j.jss.2013.12.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 12/25/2013] [Accepted: 12/30/2013] [Indexed: 11/22/2022]
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14
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Mocchegiani E, Costarelli L, Giacconi R, Malavolta M, Basso A, Piacenza F, Ostan R, Cevenini E, Gonos ES, Monti D. Micronutrient-gene interactions related to inflammatory/immune response and antioxidant activity in ageing and inflammation. A systematic review. Mech Ageing Dev 2014; 136-137:29-49. [PMID: 24388876 DOI: 10.1016/j.mad.2013.12.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 12/06/2013] [Accepted: 12/20/2013] [Indexed: 02/07/2023]
Abstract
Recent longitudinal studies in dietary daily intake in human centenarians have shown that a satisfactory content of some micronutrients within the cells maintain several immune functions, a low grade of inflammation and preserve antioxidant activity. Micronutrients (zinc, copper, selenium) play a pivotal role in maintaining and reinforcing the performances of the immune and antioxidant systems as well as in affecting the complex network of the genes (nutrigenomic) with anti- and pro-inflammatory tasks. Genes of pro- and anti-inflammatory cytokines and some key regulators of trace elements homeostasis, such as Metallothioneins (MT), are involved in the susceptibility to major geriatric disease/disorders. Moreover, the genetic inter-individual variability may affect the nutrients' absorption (nutrigenetic) with altered effects on inflammatory/immune response and antioxidant activity. The interaction between genetic factors and micronutrients (nutrigenomic and nutrigenetic approaches) may influence ageing and longevity because the micronutrients may become also toxic. This review reports the micronutrient-gene interactions in ageing and their impact on the healthy state with a focus on the method of protein-metal speciation analysis. The association between micronutrient-gene interactions and the protein-metal speciation analysis can give a complete picture for a personalized nutrient supplementation or chelation in order to reach healthy ageing and longevity.
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Affiliation(s)
- Eugenio Mocchegiani
- Translation Center of Research in Nutrition and Ageing, Scientific and Technological Pole, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121 Ancona, Italy.
| | - Laura Costarelli
- Translation Center of Research in Nutrition and Ageing, Scientific and Technological Pole, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121 Ancona, Italy
| | - Robertina Giacconi
- Translation Center of Research in Nutrition and Ageing, Scientific and Technological Pole, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121 Ancona, Italy
| | - Marco Malavolta
- Translation Center of Research in Nutrition and Ageing, Scientific and Technological Pole, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121 Ancona, Italy
| | - Andrea Basso
- Translation Center of Research in Nutrition and Ageing, Scientific and Technological Pole, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121 Ancona, Italy
| | - Francesco Piacenza
- Translation Center of Research in Nutrition and Ageing, Scientific and Technological Pole, Italian National Research Centres on Ageing (INRCA), Via Birarelli 8, 60121 Ancona, Italy
| | - Rita Ostan
- Department of Experimental Diagnostic and Specialty Medicine (DIMES) and Interdepartmental Centre "L. Galvani" (CIG), University of Bologna, Via San Giacomo, 12, 40126 Bologna, Italy
| | - Elisa Cevenini
- Department of Experimental Diagnostic and Specialty Medicine (DIMES) and Interdepartmental Centre "L. Galvani" (CIG), University of Bologna, Via San Giacomo, 12, 40126 Bologna, Italy
| | - Efstathios S Gonos
- National Hellenic Research Foundation, Institute of Biology, Medicinal Chemistry and Biotechnology, 48 Vas. Constantinou Ave., Athens 11635, Greece
| | - Daniela Monti
- Department of Clinical and Experimental Biomedical Sciences, University of Florence, Viale Morgagni, 50, 50134 Florence, Italy
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15
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Micronutrient (Zn, Cu, Fe)-gene interactions in ageing and inflammatory age-related diseases: implications for treatments. Ageing Res Rev 2012; 11:297-319. [PMID: 22322094 DOI: 10.1016/j.arr.2012.01.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 01/20/2012] [Accepted: 01/23/2012] [Indexed: 02/07/2023]
Abstract
In ageing, alterations in inflammatory/immune response and antioxidant capacity lead to increased susceptibility to diseases and loss of mobility and agility. Various essential micronutrients in the diet are involved in age-altered biological functions. Micronutrients (zinc, copper, iron) play a pivotal role either in maintaining and reinforcing the immune and antioxidant performances or in affecting the complex network of genes (nutrigenomic approach) involved in encoding proteins for a correct inflammatory/immune response. By the other side, the genetic inter-individual variability may affect the absorption and uptake of the micronutrients (nutrigenetic approach) with subsequent altered effects on inflammatory/immune response and antioxidant activity. Therefore, the individual micronutrient-gene interactions are fundamental to achieve healthy ageing. In this review, we report and discuss the role of micronutrients (Zn, Cu, Fe)-gene interactions in relation to the inflammatory status and the possibility of a supplement in the event of a micronutrient deficiency or chelation in presence of micronutrient overload in relation to specific polymorphisms of inflammatory proteins or proteins related of the delivery of the micronutriemts to various organs and tissues. In this last context, we report the protein-metal speciation analysis in order to have, coupled with micronutrient-gene interactions, a more complete picture of the individual need in micronutrient supplementation or chelation to achieve healthy ageing and longevity.
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16
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Ramanathan G, Atchison WD. Ca2+ entry pathways in mouse spinal motor neurons in culture following in vitro exposure to methylmercury. Neurotoxicology 2011; 32:742-50. [PMID: 21839771 DOI: 10.1016/j.neuro.2011.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 06/06/2011] [Accepted: 07/13/2011] [Indexed: 12/29/2022]
Abstract
Methylmercury (MeHg) is a widespread environmental toxicant with major actions on the central nervous system. Among the neurons reportedly affected in cases of Hg poisoning are motor neurons; however, the direct cellular effects of MeHg on motor neurons have not been reported. Ratiometric fluorescence imaging, using the Ca(2+)-sensitive fluorophore fura-2, was used to examine the effect of MeHg on Ca(2+) homeostasis in primary cultures of mouse spinal motor neurons. In vitro MeHg exposure at concentrations (0.1-2 μM) known to affect other neurons in culture differentially, induced a biphasic rise in fura-2 fluorescence ratio indicating an increase in [Ca(2+)](i). The time-to-onset of these fura-2 fluorescence ratio changes was inversely correlated with MeHg concentration. TPEN (20 μM), a non-Ca(2+), divalent cation chelator, reduced the amplitude of the increase in fura-2 fluorescence induced by MeHg in the first phase, indicating that both Ca(2+) and non-Ca(2+) divalent cations contribute to the MeHg-induced effect. When examining various Ca(2+) entry pathways as possible targets contributing to Ca(2+) influx, we found that excitatory amino acid receptor blockers MK-801 (15 μM), and AP-5 (100 μM)-both NMDA receptor-operated ion channel blockers, CNQX (20 μM), a non-NMDA receptor blocker, and the voltage-dependent Ca(2+) channel blockers nifedipine (1 μM) and ω-conotoxin-GVIA (1 μM) all significantly delayed the development of increased Ca(2+) caused by MeHg. The voltage-dependent Na(+) channel blocker tetrodotoxin (TTX, 1 μM) did not alter the MeHg-induced increases in fura-2 fluorescence ratio. Thus, MeHg alters Ca(2+) homeostasis in mouse spinal motor neurons through excitatory amino acid receptor-mediated pathways, and nifedipine and ω-conotoxin-GVIA-sensitive pathways. Spinal motor neurons are highly sensitive to this effect of acute exposure to MeHg.
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Affiliation(s)
- Gunasekaran Ramanathan
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA
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