1
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Gomez-Lopez S, Serrano R, Cohen B, Martinez-Argudo I, Lopez-Sanz L, Guadamillas MC, Calero R, Ruiz MJ. Novel Titanocene Y derivative with albumin affinity exhibits improved anticancer activity against platinum resistant cells. J Inorg Biochem 2024; 254:112520. [PMID: 38460481 DOI: 10.1016/j.jinorgbio.2024.112520] [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: 12/21/2023] [Revised: 03/01/2024] [Accepted: 03/04/2024] [Indexed: 03/11/2024]
Abstract
The antitumor activity of Ti(IV)-based compounds put them in the spotlight for cancer treatment in the past, but their lack of stability in vivo due to a high rate of hydrolysis has hindered their development as antitumor drugs. As a possible solution for this problem, we have reported a synthesis strategy through which we combined a titanocene fragment, a tridentate ligand, and a long aliphatic chain. This strategy allowed us to generate a titanium compound (Myr-Ti) capable of interacting with albumin, highly stable in water and with cytotoxic activity in tumor cells[1]. Following a similar strategy, now we report the synthesis of a new compound (Myr-TiY) derived from titanocene Y that shows antitumoral activity in a cisplatin resistant model with a 50% inhibitory concentration (IC50) of 41-76 μM. This new compound shows high stability and a strong interaction with human serum albumin. Myr-TiY has a significant antiproliferative and proapoptotic effect on the tested cancer cells and shows potential tumor selectivity when assayed in non-tumor human epithelial cells being more selective (1.3-3.8 times) for tumor cells than cisplatin. These results lead us to think that the described synthesis strategy could be useful to generate compounds for the treatment of both cisplatin-sensitive and cisplatin-resistant cancers.
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Affiliation(s)
- Sergio Gomez-Lopez
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Rosario Serrano
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; Departamento de Química Orgánica, Inorgánica y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Boiko Cohen
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; Departamento de Química Física, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; INAMOL, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Isabel Martinez-Argudo
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Laura Lopez-Sanz
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Marta Carmen Guadamillas
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Raul Calero
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; Departamento de Química Orgánica, Inorgánica y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
| | - Maria Jose Ruiz
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; Departamento de Química Orgánica, Inorgánica y Bioquímica, Universidad de Castilla-La Mancha, 45071 Toledo, Spain; INAMOL, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
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2
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Musa M, Abid M, Bradshaw TD, Boocock DJ, Coveney C, Argent SP, Woodward S. Probing the Mechanism of Action of Bis(phenolato) Amine (ONO Donor Set) Titanium(IV) Anticancer Agents. J Med Chem 2024; 67:2732-2744. [PMID: 38331433 PMCID: PMC10895680 DOI: 10.1021/acs.jmedchem.3c01874] [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: 02/10/2024]
Abstract
The need for anticancer therapies that overcome metallodrug resistance while minimizing adverse toxicities is targeted, herein, using titanium coordination complexes. Octahedral titanium(IV) trans,mer-[Ti{R1N(CH2-2-MeO-4-R1-C6H2)2}2] [R1 = Et, allyl, n-Pr, CHO, F, CH2(morpholino), the latter from the formyl derivative; R2 = Me, Et; not all combinations] are attained from Mannich reactions of commercial 2-methoxyphenols (27-74% overall yield, 2 steps). These crystalline (four X-ray structures) Ti(IV)-complexes are active against MCF-7, HCT-116, HT-29, PANC-1, and MDA-MB-468 cancer cell lines (GI50 = 0.5-38 μM). Their activity and cancer selectivity (vs nontumor MRC-5 cells) typically exceeds that of cisplatin (up to 16-fold). Proteomic analysis (in MCF-7) supported by other studies (G2/M cell cycle arrest, ROS generation, γH2AX production, caspase activation, annexin positivity, western blot, and kinase screens in MCF-7 and HCT-116) suggest apoptosis elicited by more than one mechanism of action. Comparison of these data to the modes of action proposed for salan Ti(IV) complexes is made.
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Affiliation(s)
- Mustapha Musa
- GSK Carbon Neutral Laboratories for Sustainable Chemistry, University of Nottingham, Triumph Road, Nottingham NG7 2TU, U.K
| | - Mohammed Abid
- Department of Chemistry, College of Science, University of Anbar, Anbarshire 31001, Iraq
| | - Tracey D Bradshaw
- BDI, School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, U.K
| | - David J Boocock
- School of Science and Technology, Nottingham Trent University, Clifton, Nottingham NG11 8NS, U.K
| | - Clare Coveney
- School of Science and Technology, Nottingham Trent University, Clifton, Nottingham NG11 8NS, U.K
| | - Stephen P Argent
- School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, U.K
| | - Simon Woodward
- GSK Carbon Neutral Laboratories for Sustainable Chemistry, University of Nottingham, Triumph Road, Nottingham NG7 2TU, U.K
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3
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Borutzki Y, Skos L, Gerner C, Meier‐Menches SM. Exploring the Potential of Metal-Based Candidate Drugs as Modulators of the Cytoskeleton. Chembiochem 2023; 24:e202300178. [PMID: 37345897 PMCID: PMC10946712 DOI: 10.1002/cbic.202300178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 06/23/2023]
Abstract
During recent years, accumulating evidence suggested that metal-based candidate drugs are promising modulators of cytoskeletal and cytoskeleton-associated proteins. This was substantiated by the identification and validation of actin, vimentin and plectin as targets of distinct ruthenium(II)- and platinum(II)-based modulators. Despite this, structural information about molecular interaction is scarcely available. Here, we compile the scattered reports about metal-based candidate molecules that influence the cytoskeleton, its associated proteins and explore their potential to interfere in cancer-related processes, including proliferation, invasion and the epithelial-to-mesenchymal transition. Advances in this field depend crucially on determining binding sites and on gaining comprehensive insight into molecular drug-target interactions. These are key steps towards establishing yet elusive structure-activity relationships.
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Affiliation(s)
- Yasmin Borutzki
- Institute of Inorganic ChemistryFaculty of ChemistryUniversity of Vienna1090ViennaAustria
- Department of Analytical ChemistryFaculty of ChemistryUniversity of Vienna1090ViennaAustria
- Doctoral School of ChemistryUniversity of Vienna1090ViennaAustria
| | - Lukas Skos
- Department of Analytical ChemistryFaculty of ChemistryUniversity of Vienna1090ViennaAustria
- Doctoral School of ChemistryUniversity of Vienna1090ViennaAustria
| | - Christopher Gerner
- Department of Analytical ChemistryFaculty of ChemistryUniversity of Vienna1090ViennaAustria
- Joint Metabolome FacilityUniversity of Vienna and Medical University Vienna1090ViennaAustria
| | - Samuel M. Meier‐Menches
- Institute of Inorganic ChemistryFaculty of ChemistryUniversity of Vienna1090ViennaAustria
- Department of Analytical ChemistryFaculty of ChemistryUniversity of Vienna1090ViennaAustria
- Joint Metabolome FacilityUniversity of Vienna and Medical University Vienna1090ViennaAustria
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4
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Ge T, Shao Y, Bao X, Xu W, Lu C. Cellular senescence in liver diseases: From mechanisms to therapies. Int Immunopharmacol 2023; 121:110522. [PMID: 37385123 DOI: 10.1016/j.intimp.2023.110522] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 06/05/2023] [Accepted: 06/14/2023] [Indexed: 07/01/2023]
Abstract
Cellular senescence is an irreversible state of cell cycle arrest, characterized by a gradual decline in cell proliferation, differentiation, and biological functions. Cellular senescence is double-edged for that it can provoke organ repair and regeneration in physiological conditions but contribute to organ and tissue dysfunction and prime multiple chronic diseases in pathological conditions. The liver has a strong regenerative capacity, where cellular senescence and regeneration are closely involved. Herein, this review firstly introduces the morphological manifestations of senescent cells, the major regulators (p53, p21, and p16), and the core pathophysiologic mechanisms underlying senescence process, and then specifically generalizes the role and interventions of cellular senescence in multiple liver diseases, including alcoholic liver disease, nonalcoholic fatty liver disease, liver fibrosis, and hepatocellular carcinoma. In conclusion, this review focuses on interpreting the importance of cellular senescence in liver diseases and summarizes potential senescence-related regulatory targets, aiming to provide new insights for further researches on cellular senescence regulation and therapeutic developments for liver diseases.
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Affiliation(s)
- Ting Ge
- School of Pharmacy, Nantong University, Nantong, Jiangsu, China
| | - Yunyun Shao
- School of Pharmacy, Nantong University, Nantong, Jiangsu, China
| | - Xiaofeng Bao
- School of Pharmacy, Nantong University, Nantong, Jiangsu, China
| | - Wenxuan Xu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China.
| | - Chunfeng Lu
- School of Pharmacy, Nantong University, Nantong, Jiangsu, China.
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5
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Serrano R, Martinez-Argudo I, Fernandez-Sanchez M, Pacheco-Liñan PJ, Bravo I, Cohen B, Calero R, Ruiz MJ. New titanocene derivative with improved stability and binding ability to albumin exhibits high anticancer activity. J Inorg Biochem 2021; 223:111562. [PMID: 34364140 DOI: 10.1016/j.jinorgbio.2021.111562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 07/23/2021] [Accepted: 07/30/2021] [Indexed: 11/15/2022]
Abstract
Titanium-based therapies have emerged as a promising alternative for the treatment of cancer patients, particularly those with cisplatin resistant tumors. Unfortunately, some titanium compounds show stability and solubility problems that have hindered their use in clinical practice. Here, we designed and synthesized a new titanium complex containing a titanocene fragment, a tridentate ligand to improve its stability in water, and a long aliphatic chain, designed to facilitate a non-covalent interaction with albumin, the most abundant protein in human serum. The stability and human serum albumin affinity of the resulting titanium complex was investigated by UV-Vis absorption and fluorescence spectroscopy techniques. Complex [TiCp2{(OOC)2py-O-myr}] (3) (myr = C14H29, py = pyridine) and its analogous [TiCp2{(OOC)2py-OH}] (4), lacking the aliphatic chain, showed improved stability in phosphate saline buffer compared with [TiCp2Cl2] (1). 3 showed a strong interaction with human serum albumin in a 1:1 stoichiometry. The cytotoxic effect of 3 was higher compared to [TiCp2Cl2] in tumor cell lines and showed potential tumor selectivity when assayed in non-tumor human epithelial cells. Finally, 3 showed an antiproliferative effect on cancer cells, decreasing the population in the S phase, and increasing apoptotic cells in a significant manner. All this makes the novel Ti(IV) compound 3 a firm candidate to continue further studies of its therapeutic potential in vitro and in vivo.
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Affiliation(s)
- Rosario Serrano
- Universidad de Castilla-La Mancha, Facultad de Ciencias Ambientales y Bioquímica, 45071 Toledo, Spain; Universidad de Castilla-La Mancha, Departamento de Química Orgánica, Inorgánica y Bioquímica, Spain
| | - Isabel Martinez-Argudo
- Universidad de Castilla-La Mancha, Facultad de Ciencias Ambientales y Bioquímica, 45071 Toledo, Spain; Universidad de Castilla-La Mancha, Departamento de Ciencia y Tecnología Agroforestal y Genética, Spain
| | - Miguel Fernandez-Sanchez
- Universidad de Castilla-La Mancha, Facultad de Ciencias Ambientales y Bioquímica, 45071 Toledo, Spain
| | - Pedro J Pacheco-Liñan
- Universidad de Castilla-La Mancha, Facultad de Farmacia, 02071 Albacete, Spain; Universidad de Castilla-La Mancha, Departamento de Química Física, Spain
| | - Ivan Bravo
- Universidad de Castilla-La Mancha, Facultad de Farmacia, 02071 Albacete, Spain; Universidad de Castilla-La Mancha, Departamento de Química Física, Spain
| | - Boiko Cohen
- Universidad de Castilla-La Mancha, Facultad de Ciencias Ambientales y Bioquímica, 45071 Toledo, Spain; Universidad de Castilla-La Mancha, Departamento de Química Física, Spain; Universidad de Castilla-La Mancha, INAMOL, 45071 Toledo, Spain
| | - Raul Calero
- Universidad de Castilla-La Mancha, Facultad de Ciencias Ambientales y Bioquímica, 45071 Toledo, Spain; Universidad de Castilla-La Mancha, Departamento de Química Orgánica, Inorgánica y Bioquímica, Spain.
| | - Maria Jose Ruiz
- Universidad de Castilla-La Mancha, Facultad de Ciencias Ambientales y Bioquímica, 45071 Toledo, Spain; Universidad de Castilla-La Mancha, Departamento de Química Orgánica, Inorgánica y Bioquímica, Spain
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6
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Zhao T, Wang P, Ji M, Li S, Yang M, Pu X. Post-Synthetic Modification Research of Salan Titanium bis-Chelates via Sonogashira Reaction. ACTA CHIMICA SINICA 2021. [DOI: 10.6023/a21060282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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7
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Abid M, Nouch R, Bradshaw TD, Lewis W, Woodward S. Tripodal O-N-O Bis
-Phenolato Amine Titanium(IV) Complexes Show High in vitro Anti-Cancer Activity. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900510] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Mohammed Abid
- Department of Chemistry; College of Science; University of Anbar; Western side of Ramadi City Anbarshire Republic of Iraq
- GSK Carbon Neutral Laboratories for Sustainable Chemistry; University of Nottingham; Triumph Road Nottingham NG7 2TU United Kingdom
| | - Ryan Nouch
- GSK Carbon Neutral Laboratories for Sustainable Chemistry; University of Nottingham; Triumph Road Nottingham NG7 2TU United Kingdom
| | - Tracey D. Bradshaw
- School of Pharmacy, Centre for Biomolecular Sciences; College of Science; University Park Nottingham NG7 2RD United Kingdom
| | - William Lewis
- GSK Carbon Neutral Laboratories for Sustainable Chemistry; University of Nottingham; Triumph Road Nottingham NG7 2TU United Kingdom
| | - Simon Woodward
- GSK Carbon Neutral Laboratories for Sustainable Chemistry; University of Nottingham; Triumph Road Nottingham NG7 2TU United Kingdom
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8
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Luo X, Zhang X, Gan L, Zhou C, Zhao T, Zeng T, Liu S, Xiao Y, Yu J, Zhao F. The outer membrane protein Tp92 of Treponema pallidum induces human mononuclear cell death and IL-8 secretion. J Cell Mol Med 2018; 22:6039-6054. [PMID: 30596396 PMCID: PMC6237608 DOI: 10.1111/jcmm.13879] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 07/30/2018] [Indexed: 12/19/2022] Open
Abstract
Treponema pallidum is the pathogen that causes syphilis, a sexually transmitted disease; however, the pathogenic mechanism of this organism remains unclear. Tp92 is the only T. pallidum outer membrane protein that has structural features similar to the outer membrane proteins of other Gram-negative bacteria, but the exact functions of this protein remain unknown. In the present study, we demonstrated that the recombinant Tp92 protein can induce human mononuclear cell death. Tp92 mediated the human monocytic cell line derived from an acute monicytic leukemia patient (THP-1) cell death by recognizing CD14 and/or TLR2 on cell surfaces. After the stimulation of THP-1 cells by the Tp92 protein, Tp92 may induce atypical pyroptosis of THP-1 cells via the pro-caspase-1 pathway. Meanwhile, this protein caused the apoptosis of THP-1 cells via the receptor-interacting protein kinase 1/caspase-8/aspase-3 pathway. Tp92 reduced the number of monocytes among peripheral blood mononuclear cells. Interestingly, further research showed that Tp92 failed to increase the tumour necrosis factor-α, interleukin (IL)-1β, IL-6, IL-10, IL-18 and monocyte chemotactic protein 1 (MCP)-1 levels but slightly elevated the IL-8 levels via the Nuclear Factor (NF)-κB pathway in THP-1 cells. The data suggest that Tp92 recognizes CD14 and TLR2, transfers the signal to a downstream pathway, and activates NF-κB to mediate the production of IL-8. This mechanism may help T. pallidum escape recognition and elimination by the host innate immune system.
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MESH Headings
- Antigens, Surface/genetics
- Bacterial Proteins/genetics
- Caspase 1/genetics
- Cell Death/genetics
- Cell Line, Tumor
- Cytokines/genetics
- Host-Pathogen Interactions/genetics
- Humans
- Interleukin-8/genetics
- Leukemia, Monocytic, Acute/genetics
- Leukemia, Monocytic, Acute/microbiology
- Leukemia, Monocytic, Acute/pathology
- Leukocytes, Mononuclear/microbiology
- Leukocytes, Mononuclear/pathology
- Lipopolysaccharide Receptors/genetics
- NF-kappa B/genetics
- Recombinant Proteins/genetics
- Signal Transduction/genetics
- Syphilis/genetics
- Syphilis/microbiology
- Syphilis/pathology
- Toll-Like Receptor 2/genetics
- Treponema pallidum/genetics
- Treponema pallidum/pathogenicity
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Affiliation(s)
- Xi Luo
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
| | - Xiaohong Zhang
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
- Department of Histology and EmbryologySchool of MedicineUniversity of South ChinaHengyangChina
| | - Lin Gan
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
| | - Chenglong Zhou
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
| | - Tie Zhao
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
| | - Tiebing Zeng
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
| | - Shuangquan Liu
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
- Department of Clinical LaboratoryThe First Affiliated Hospital of University of South ChinaHengyangChina
| | - Yongjian Xiao
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
- Department of Clinical LaboratoryThe Second Affiliated Hospital of University of South ChinaHengyangChina
| | - Jian Yu
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
| | - Feijun Zhao
- Institute of Pathogenic Biology and Key Laboratory of Special Pathogen Prevention and Control of Hunan ProvinceCollaborative Innovation Center for New Molecular Drug ResearchUniversity of South ChinaHengyangChina
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Miller-Shakesby DM, Nigam S, Hughes DL, Lopez-Estelles E, Elsegood MRJ, Cawthorne CJ, Archibald SJ, Redshaw C. Synthesis, crystal structure, and cytotoxicity studies of titanacalix[4 and 8]arene complexes. Dalton Trans 2018; 47:8992-8999. [PMID: 29922776 DOI: 10.1039/c8dt01992d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Reaction of 5,11,17,23-tetra-tert-butyl-dihydroxy-26,28-bis(2-pentoxy)calix[4]arene (L(OH)2(Opentyl)2) with [TiCl4] afforded the dichlorotitanoacalix[4]arene complex [TiCl2L(O)2(Opentyl)2] (1) in good yield. Hydrolysis of 1 led to the isolation of the complex {[TiL(O)3(Opentyl)]2(μ-OH)(μ-Cl)} (2). Reaction of 5,11,17,23,29,35,41,47-p-tert-butyl-49,50,51,52,53,54,55,56-octapropoxycalix[8]arene (L'(Opropyl)8) with [TiCl4] in refluxing toluene afforded, following work-up, a 35 : 65 mixture (3) of the complex [Ti(NCMe)Cl]2[TiCl(μ-O)]2L' and the silicone grease derived complex [Ti(NCMe)Cl]2[Ti(μ-O)]2[OSi(CH3)2OSi(CH3)2O]L' in which the grease replaces two chloride ligands. The molecular structures of 1·2MeCN, 2·7¼MeCN, and 3·10MeCN have been determined. The complexes were studied using in vitro cell assays and were found to have CC50 values in the range 111-186 μM, i.e. they have low toxicity.
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Affiliation(s)
- David M Miller-Shakesby
- Chemistry, School of Mathematics and Physical Sciences, University of Hull, Hull, HU6 7RX, UK.
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10
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The relationship between vacuolation and initiation of PCD in rice (Oryza sativa) aleurone cells. Sci Rep 2017; 7:41245. [PMID: 28117452 PMCID: PMC5259747 DOI: 10.1038/srep41245] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 12/19/2016] [Indexed: 02/05/2023] Open
Abstract
Vacuole fusion is a necessary process for the establishment of a large central vacuole, which is the central location of various hydrolytic enzymes and other factors involved in death at the beginning of plant programmed cell death (PCD). In our report, the fusion of vacuoles has been presented in two ways: i) small vacuoles coalesce to form larger vacuoles through membrane fusion, and ii) larger vacuoles combine with small vacuoles when small vacuoles embed into larger vacuoles. Regardless of how fusion occurs, a large central vacuole is formed in rice (Oryza sativa) aleurone cells. Along with the development of vacuolation, the rupture of the large central vacuole leads to the loss of the intact plasma membrane and the degradation of the nucleus, resulting in cell death. Stabilizing or disrupting the structure of actin filaments (AFs) inhibits or promotes the fusion of vacuoles, which delays or induces PCD. In addition, the inhibitors of the vacuolar processing enzyme (VPE) and cathepsin B (CathB) block the occurrence of the large central vacuole and delay the progression of PCD in rice aleurone layers. Overall, our findings provide further evidence for the rupture of the large central vacuole triggering the PCD in aleruone layers.
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