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Krochtová K, Janovec L, Bogárová V, Halečková A, Kožurková M. Interaction of 3,9-disubstituted acridine with single stranded poly(rA), double stranded poly(rAU) and triple stranded poly(rUAU): molecular docking - A spectroscopic tandem study. Chem Biol Interact 2024; 394:110965. [PMID: 38552767 DOI: 10.1016/j.cbi.2024.110965] [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: 01/26/2024] [Revised: 03/12/2024] [Accepted: 03/16/2024] [Indexed: 04/10/2024]
Abstract
RNA plays an important role in many biological processes which are crucial for cell survival, and it has been suggested that it may be possible to inhibit individual processes involved in many diseases by targeting specific sequences of RNA. The aim of this work is to determine the affinity of novel 3,9-disubstited acridine derivative 1 with three different RNA molecules, namely single stranded poly(rA), double stranded homopolymer poly(rAU) and triple stranded poly(rUAU). The results of the absorption titration assays show that the binding constant of the novel derivative to the RNA molecules was in the range of 1.7-6.2 × 104 mol dm-3. The fluorescence and circular dichroism titration assays revealed considerable changes. The most significant results in terms of interpreting the nature of the interactions were the melting temperatures of the RNA samples in complexes with the 1. In the case of poly(rA), denaturation resulted in a self-structure formation; increased stabilization was observed for poly(rAU), while the melting points of the ligand-poly(rUAU) complex showed significant destabilization as a result of the interaction. The principles of molecular mechanics were applied to propose the non-bonded interactions within the binding complex, pentariboadenylic acid and acridine ligand as the study model. Initial molecular docking provided the input structure for advanced simulation techniques. Molecular dynamics simulation and cluster analysis reveal π - π stacking and the hydrogen bonds formation as the main forces that can stabilize the binding complex. Subsequent MM-GBSA calculations showed negative binding enthalpy accompanied the complex formation and proposed the most preferred conformation of the interaction complex.
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Affiliation(s)
- Kristína Krochtová
- Department of Biochemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Šrobárova 2, 041 54, Košice, Slovak Republic
| | - Ladislav Janovec
- Department of Organic Chemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Šrobárova 2, 041 54, Košice, Slovak Republic
| | - Viktória Bogárová
- Department of Biochemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Šrobárova 2, 041 54, Košice, Slovak Republic
| | - Annamária Halečková
- Department of Organic Chemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Šrobárova 2, 041 54, Košice, Slovak Republic
| | - Mária Kožurková
- Department of Biochemistry, Institute of Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Šrobárova 2, 041 54, Košice, Slovak Republic.
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2
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Gasmi A, Asghar F, Zafar S, Oliinyk P, Khavrona O, Lysiuk R, Peana M, Piscopo S, Antonyak H, Pen JJ, Lozynska I, Noor S, Lenchyk L, Muhammad A, Vladimirova I, Dub N, Antoniv O, Tsal O, Upyr T, Bjørklund G. Berberine: Pharmacological Features in Health, Disease and Aging. Curr Med Chem 2024; 31:1214-1234. [PMID: 36748808 DOI: 10.2174/0929867330666230207112539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 12/15/2022] [Accepted: 12/29/2022] [Indexed: 02/08/2023]
Abstract
BACKGROUND Berberine is the main active compound of different herbs and is defined as an isoquinoline quaternary botanical alkaloid found in barks and roots of numerous plants. It exhibits a wide range of pharmacological effects, such as anti-obesity and antidiabetic effects. Berberine has antibacterial activity against a variety of microbiota, including many bacterial species, protozoa, plasmodia, fungi, and trypanosomes. OBJECTIVE This review describes the role of berberine and its metabolic effects. It also discusses how it plays a role in glucose metabolism, fat metabolism, weight loss, how it modulates the gut microbiota, and what are its antimicrobial properties along with its potential side effects with maximal tolerable dosage. METHODS Representative studies were considered and analyzed from different scientific databases, including PubMed and Web of Science, for the years 1982-2022. RESULTS Literature analysis shows that berberine affects many biochemical and pharmacological pathways that theoretically yield a positive effect on health and disease. Berberine exhibits neuroprotective properties in various neurodegenerative and neuropsychological ailments. Despite its low bioavailability after oral administration, berberine is a promising tool for several disorders. A possible hypothesis would be the modulation of the gut microbiome. While the evidence concerning the aging process in humans is more limited, preliminary studies have shown positive effects in several models. CONCLUSION Berberine could serve as a potential candidate for the treatment of several diseases. Previous literature has provided a basis for scientists to establish clinical trials in humans. However, for obesity, the evidence appears to be sufficient for hands-on use.
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Affiliation(s)
- Amin Gasmi
- Société Francophone de Nutrithérapie et de Nutrigénétique Appliquée, Villeurbanne, France
| | - Farah Asghar
- Department of Microbiology and Molecular Genetics (MMG), University of the Punjab, Lahore, Pakistan
| | - Saba Zafar
- Department of Research, The Women University, Multan, Pakistan
| | - Petro Oliinyk
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- CONEM Ukraine Life Science Research Group, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Oksana Khavrona
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- CONEM Ukraine Life Science Research Group, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Roman Lysiuk
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- CONEM Ukraine Life Science Research Group, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Massimiliano Peana
- Department of Chemical, Physical, Mathematical and Natural Sciences, University of Sassari, Sassari, Italy
| | - Salva Piscopo
- Société Francophone de Nutrithérapie et de Nutrigénétique Appliquée, Villeurbanne, France
| | - Halyna Antonyak
- Department of Ecology, Ivan Franko National University of Lviv, Lviv, Ukraine
| | - Joeri J Pen
- Diabetes Clinic, Department of Internal Medicine, UZ Brussel, Vrije Universiteit Brussel (VUB), Brussels, Belgium
- Department of Nutrition, UZ Brussel, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Iryna Lozynska
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- CONEM Ukraine Life Science Research Group, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Sadaf Noor
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan
| | - Larysa Lenchyk
- Department of Research, National University of Pharmacy, Kharkiv, Ukraine
- CONEM Ukraine Pharmacognosy and Natural Product Chemistry Research Group, National University of Pharmacy, Kharkiv, Ukraine
| | - Akram Muhammad
- Department of Research, Government College University, Faisalabad, Pakistan
| | - Inna Vladimirova
- Department of Research, National University of Pharmacy, Kharkiv, Ukraine
- CONEM Ukraine Pharmacognosy and Natural Product Chemistry Research Group, National University of Pharmacy, Kharkiv, Ukraine
| | - Natalia Dub
- Andrei Krupynskyi Lviv Medical Academy, Lviv, Ukraine
| | - Olha Antoniv
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- CONEM Ukraine Life Science Research Group, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Oksana Tsal
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
- CONEM Ukraine Life Science Research Group, Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Taras Upyr
- Department of Research, National University of Pharmacy, Kharkiv, Ukraine
- CONEM Ukraine Pharmacognosy and Natural Product Chemistry Research Group, National University of Pharmacy, Kharkiv, Ukraine
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine (CONEM), Mo i Rana, Norway
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3
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Yuan F, Liu X, Li J, Tan L. Interactions of arene ruthenium(II) complexes [η 6-(C 6H 6)Ru(pprip)Cl] + and [η 6-(C 6H 6)Ru(H 2iiP)Cl] + with RNA triplex poly(U)•poly(A)*poly(U). J Biol Inorg Chem 2023; 28:559-570. [PMID: 37477757 DOI: 10.1007/s00775-023-02008-y] [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: 01/10/2023] [Accepted: 06/30/2023] [Indexed: 07/22/2023]
Abstract
Two arene ruthenium(II) complexes [η6-(C6H6)Ru(pprip)Cl]PF6 (Ru1; pprip = 2-(3-phenyl-1H-pyrazol-4-yl)-imidazolo[4,5-f][1,10]phenanthroline) and [η6-(C6H6)Ru(H2iiP)Cl]PF6 (Ru2; H2iiP = 2-(indole-3-yl)-imidazolo[4,5-f][1,10]phenanthroline) have been synthesized and characterized in this work. Binding properties of Ru1 and Ru2 with the triplex RNA poly(U)•poly(A)*poly(U) were investigated by spectrophotometry and spectrofluorometry as well as viscosimetry. Analysis of spectroscopic titrations and viscosity measurements show that the two complexes bind with the triplex through intercalation, while the binding affinity for Ru2 toward the triplex is stronger than that for Ru1. Melting experiments indicate that the stabilizing effects of Ru1 and Ru2 toward the triplex differ from each other. Under the conditions used herein, Ru1 only stabilizes the Hoogsteen base-paired strand (third strand) without affecting stabilization of the Watson-Crick base-paired strand (the template duplex) of the triplex, while Ru2 stabilizes both the template duplex and the third strand. Although the two complexes prefer to stabilizing the third strand rather than the template duplex, the third-strand stabilization effect of Ru2 is stronger than that of Ru1. The obtained results of this work reveal that the planarity of the intercalative ligands plays an important role in the triplex stabilization by arene Ru(II) complexes.
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Affiliation(s)
- Feng Yuan
- College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Juan Li
- Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, People's Republic of China.
| | - Lifeng Tan
- Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, People's Republic of China.
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4
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Wen B, Liu X, Tan L. Binding and stabilizating effect of RNA triplex poly(U)⋅poly(A)*poly(U) by enantiomers of ruthenium(II) polypyridyl complex [Ru(bpy) 2(dppx)] 2. J Biol Inorg Chem 2023:10.1007/s00775-023-02004-2. [PMID: 37452869 DOI: 10.1007/s00775-023-02004-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 05/10/2023] [Indexed: 07/18/2023]
Abstract
Two chiral ruthenium(II) polypyridyl complexes, Λ-[Ru(bpy)2(dppx)]2+ (bpy = 2,2'-bipyridine, dppx = 7,8-dimethyldipyridophenazine; Λ-1) and Δ-[Ru(bpy)2(dppx)]2+ (Δ-1) have been synthesized and characterized in this work. Interactions of Λ-1 and Δ-1 with the RNA triplex poly(U)⋅poly(A)*poly(U) have been investigated by various biophysical techniques. Spectrophotometric titrations and viscosity measurements suggested that enantiomers Λ-1 and Δ-1 bind with the triplex through intercalation, while the binding strengths of the two enantiomers toward the triplex differed only slightly from each other. Fluorescence titrations showed that although enantiomers Λ-1 and Δ-1 exhibited molecular "light switch" effects toward the triplex, the effect of Δ-1 was more marked. Furthermore, Furthermore, thermal denaturation showed that the two enantiomers have significantly different stabilizing effects on the triplex. The obtained results indicate that the racemic complex [Ru(bpy)2(dppx)]2+ is similar to a non-specific metallointercalator for the triplex investigated in this study, and chiralities of Ru(II) polypyridine complexes have an important influence on the binding and stabilizing effects of enantiomers toward the triplex. Two chiral ruthenium(II) polypyridyl complexes, Λ-[Ru(bpy)2(dppx)]2+ (bpy = 2,2'-bipyridine, dppx = 7,8-dimethyldipyridophenazine; Λ-1) and Δ-[Ru(bpy)2(dppx)]2+ (Δ-1) have been synthesized and characterized in this work. Interactions of Λ-1 and Δ-1 with the RNA triplex poly(U)⋅poly(A)*poly(U) have been investigated by various biophysical techniques. The obtained results indicate that the racemic complex [Ru(bpy)2(dppx)]2+ is similar as a non-specific metallointercalator for the triplex investigated in this study, and chiralities of Ru(II) polypyridine complexes have an important influence on the binding and stabilizing effects of enantiomers toward the triplex.
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Affiliation(s)
- Bingxin Wen
- College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, People's Republic of China.
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5
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Yuan F, Liu X, Tan L. Binding and stabilization effect of arene ruthenium(Ⅱ) polypyridyl complexes toward the triple-helical RNA poly(U)•poly(A)⁎poly(U). Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.121140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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6
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Zhang C, Liu X, Tan L. Interaction of arene ruthenium(II) complexes [(η 6-C 6H 6)Ru(L)Cl]PF 6 (L = o-fpip and p-fpip) with the RNA triplex poly(U)*poly(A)•poly(U). J Inorg Biochem 2022; 232:111813. [PMID: 35405487 DOI: 10.1016/j.jinorgbio.2022.111813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/26/2022] [Accepted: 03/31/2022] [Indexed: 11/25/2022]
Abstract
To comprehend the binding properties of η6-arene Ru(II) complexes with poly(U)*poly(A)•poly(U) triplex, two arene Ru(II) complexes with different fluorine substituent positions, [(η6-C6H6)Ru(o-fpip)Cl]PF6 (Ru1,η6-C6H6 = benzene ring, o-fpip = 2-(2'‑fluorine) imidazo [4,5-f] Biver et al. (2008), Gupta et al. (2012) [1, 10] phenanthroline) and [(η6-C6H6)Ru(p-fpip)Cl]PF6 (Ru2,η6-C6H6 = benzene ring, o-fpip = 2-(4'‑fluorine) imidazo [4,5-f] Biver et al. (2008), Gupta et al. (2012) [1, 10] phenanthroline), have been synthesized and characterized in this study. The binding of Ru1 and Ru2 with poly(U)*poly(A)•poly(U) triplex has been investigated by viscosity measurement and spectroscopic methods. Analysis of UV-Vis absorption spectral titrations suggests that Ru1 and Ru2 bind to the triplex through an intercalative mode, but the binding affinity of Ru2 is slightly higher than that of Ru1, which is also verified by viscosity and EB (ethidium bromide) competition measurements. Furthermore, the thermal denaturation experiment shows that Ru1 and Ru2 increase the third-strand stabilization to a similar extent. Interestingly, the two complexes have essentially no effect on the stabilization of the template duplex. Considering the structure of Ru1 and Ru2, conceivably besides the intercalation of ligand, the force stabilizing the triplex should also involve covalent binding and electrostatic interaction. The obtained results will contribute to our understanding of the interaction of arene Ru(II) complexes with the poly(U)*poly(A)•poly(U) triplex.
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Affiliation(s)
- Chengqing Zhang
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, People's Republic of China.
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7
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Swain M, Ageeli AA, Kasprzak W, Li M, Miller JT, Sztuba-Solinska J, Schneekloth J, Koirala D, Piccirili J, Fraboni AJ, Murelli RP, Wlodawer A, Shapiro B, Baird N, Le Grice SFJ. Dynamic bulge nucleotides in the KSHV PAN ENE triple helix provide a unique binding platform for small molecule ligands. Nucleic Acids Res 2021; 49:13179-13193. [PMID: 34871450 PMCID: PMC8682744 DOI: 10.1093/nar/gkab1170] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 10/24/2021] [Accepted: 11/18/2021] [Indexed: 11/14/2022] Open
Abstract
Cellular and virus-coded long non-coding (lnc) RNAs support multiple roles related to biological and pathological processes. Several lncRNAs sequester their 3' termini to evade cellular degradation machinery, thereby supporting disease progression. An intramolecular triplex involving the lncRNA 3' terminus, the element for nuclear expression (ENE), stabilizes RNA transcripts and promotes persistent function. Therefore, such ENE triplexes, as presented here in Kaposi's sarcoma-associated herpesvirus (KSHV) polyadenylated nuclear (PAN) lncRNA, represent targets for therapeutic development. Towards identifying novel ligands targeting the PAN ENE triplex, we screened a library of immobilized small molecules and identified several triplex-binding chemotypes, the tightest of which exhibits micromolar binding affinity. Combined biophysical, biochemical, and computational strategies localized ligand binding to a platform created near a dinucleotide bulge at the base of the triplex. Crystal structures of apo (3.3 Å) and ligand-soaked (2.5 Å) ENE triplexes, which include a stabilizing basal duplex, indicate significant local structural rearrangements within this dinucleotide bulge. MD simulations and a modified nucleoside analog interference technique corroborate the role of the bulge and the base of the triplex in ligand binding. Together with recently discovered small molecules that reduce nuclear MALAT1 lncRNA levels by engaging its ENE triplex, our data supports the potential of targeting RNA triplexes with small molecules.
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MESH Headings
- Base Sequence
- Crystallography, X-Ray
- Herpesvirus 8, Human/genetics
- Herpesvirus 8, Human/metabolism
- Herpesvirus 8, Human/physiology
- Humans
- Ligands
- Molecular Docking Simulation
- Molecular Dynamics Simulation
- Molecular Structure
- Nucleic Acid Conformation
- Nucleotides/genetics
- Nucleotides/metabolism
- Poly A/chemistry
- Poly A/genetics
- Poly A/metabolism
- RNA Stability/genetics
- RNA, Long Noncoding/chemistry
- RNA, Long Noncoding/genetics
- RNA, Long Noncoding/metabolism
- RNA, Viral/chemistry
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Sarcoma, Kaposi/virology
- Small Molecule Libraries/chemistry
- Small Molecule Libraries/metabolism
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Affiliation(s)
- Monalisa Swain
- Basic Research Laboratory, National Cancer Institute, Frederick, MD 21702, USA
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Abeer A Ageeli
- Department of Chemistry & Biochemistry, University of the Sciences, Philadelphia, PA 19104, USA
- Chemistry Department, Faculty of Science (Female Section), Jazan University, Jazan 82621, Saudi Arabia
| | - Wojciech K Kasprzak
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Mi Li
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
| | - Jennifer T Miller
- Basic Research Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | | | - John S Schneekloth
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Deepak Koirala
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Joseph Piccirili
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
- Department of Chemistry, University of Chicago, Chicago, IL 60637, USA
| | - Americo J Fraboni
- Department of Chemistry, Brooklyn College, City University of New York, Brooklyn, NY, 11210, USA
| | - Ryan P Murelli
- Department of Chemistry, Brooklyn College, City University of New York, Brooklyn, NY, 11210, USA
- PhD Program in Chemistry, The Graduate Center, City University of New York, New York, NY 10016, USA
- PhD Program in Biochemistry, The Graduate Center, City University of New York, New York, NY 10016, USA
| | - Alexander Wlodawer
- Center for Structural Biology, National Cancer Institute, Frederick, MD 21702, USA
| | - Bruce A Shapiro
- RNA Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Nathan Baird
- Department of Chemistry & Biochemistry, University of the Sciences, Philadelphia, PA 19104, USA
| | - Stuart F J Le Grice
- Basic Research Laboratory, National Cancer Institute, Frederick, MD 21702, USA
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8
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Substituent effects on the interactions of ruthenium(II) polypyridyl complexes [Ru(bpy)2(6-R-dppz)]2+ (R = hydroxy and fluorine) with the RNA triplex poly(rU)·poly(rA) × poly(rU). Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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9
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Comparative studies on the binding interaction of two chiral Ru(II) polypyridyl complexes with triple- and double-helical forms of RNA. J Inorg Biochem 2020; 214:111301. [PMID: 33166867 DOI: 10.1016/j.jinorgbio.2020.111301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/12/2020] [Accepted: 10/25/2020] [Indexed: 12/27/2022]
Abstract
Two chiral Ru(II) polypyridyl complexes, Δ-[Ru(bpy)2(6-F-dppz)]2+ (Δ-1; bpy = 2,2'-bipyridine, 6-F-dppz = 6-fluorodipyrido[3,2-a:2',3'-c]phenazine) and Λ-[Ru(bpy)2(6-F-dppz)]2+ (Λ-1), have been synthesized and characterized as binders for the RNA poly(U)•poly(A)*poly(U) triplex and poly(A)•poly(U) duplex in this work. Analysis of the UV-Vis absorption spectra and fluorescence emission spectra indicates that the binding of intercalating Δ-1 with the triplex and duplex RNA is greater than that of Λ-1, while the binding affinities of the two enantiomers to triplex structure is stronger than that of duplex structure. Fluorescence titrations show that the two enantiomers can act as molecular "light switches" for triple- and double-helical RNA. Thermal denaturation studies revealed that that the two enantiomers are more stable to Watson-Crick base-paired double strand of the triplex than the Hoogsteen base-paired third strand, but their stability and selectivity are different. For Δ-enantiomer, the increase of the thermal stability of the Watson-Crick base-paired duplex (13 °C) is slightly stronger than of the Hoogsteen base-paired strand (10 °C), displaying no obvious selectivity. However, compared to the Hoogsteen base-paired strand (5 °C), the stability of the Λ-enantiomer to the Watson-Crick base-paired duplex (13 °C) is more significant, which has obvious selectivity. The overall increase in viscosity of the RNA-(Λ-1) system and its curve shape are similar to that of the RNA-(Δ-1) system, suggesting that the binding modes of two enantiomers with RNA are intercalation. The obtained results in this work may be useful for understanding the binding differences in chiral Ru(II) polypyridyl complexes toward RNA triplex and duplex.
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10
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Malina J, Farrell NP, Brabec V. Substitution-Inert Polynuclear Platinum Complexes Inhibit Reverse Transcription Preferentially in RNA Triplex-Forming Templates. Inorg Chem 2020; 59:15135-15143. [PMID: 32988198 DOI: 10.1021/acs.inorgchem.0c02070] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
RNA triplexes are significant tertiary structure motifs that are found in many functional RNAs. Hence, small molecules capable of recognition, binding, and stabilization of the triple-helical RNA structures are emerging as attractive potential molecular biology tools and therapeutic agents. Here, we utilize methods of molecular biology and biophysics to study the interactions of a series of antitumor substitution-inert polynuclear platinum complexes (SI-PPCs) with triple-helical RNA structures. We show that SI-PPCs recognize and stabilize RNA triplexes and inhibit reverse transcription preferentially in the RNA template prone to the triplex formation. These so far unexplored properties of SI-PPCs suggest that the targeting of triple-stranded regions in RNA might contribute to the biological effects of SI-PPCs.
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Affiliation(s)
- Jaroslav Malina
- Czech Academy of Sciences, Institute of Biophysics, Kralovopolska 135, Brno CZ-61265, Czech Republic
| | - Nicholas P Farrell
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284-2006, United States
| | - Viktor Brabec
- Czech Academy of Sciences, Institute of Biophysics, Kralovopolska 135, Brno CZ-61265, Czech Republic
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11
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Dong Z, Liu X, Tan L. Biophysical insights into the interaction of two enantiomers of Ru(II) complex [Ru(bpy) 2(7-CH 3-dppz)] 2+ with the RNA poly(U-A⁎U) triplex. J Biol Inorg Chem 2020; 25:1085-1095. [PMID: 33040210 DOI: 10.1007/s00775-020-01825-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 09/28/2020] [Indexed: 01/14/2023]
Abstract
To determine the factors affecting the stabilization of RNA triple-stranded structure by chiral Ru(II) polypyridyl complexes, a new pair of enantiomers, ∆-[Ru(bpy)2(7-CH3-dppz)]2+ (∆-1; bpy = 2,2'-bipyridine, 7-CH3-dppz = 7-methyl-dipyrido[3,2-a,2',3'-c]phenazine) and Λ-[Ru(bpy)2(7-CH3-dppz)]2+ (Λ-1), have been synthesized and characterized in this work. Binding properties of the two enantiomers with the RNA poly(U-A⁎U) triplex (where "-" denotes the Watson - Crick base pairing and "⁎" denotes the Hoogsteen base pairing) have been studied by spectroscopy and hydrodynamics methods. Under the conditions used in this study, changes in absorption spectra of the two enantiomers are not very different from each other when bound to the triplex, although the binding affinity of ∆-1 is higher than that of Λ-1. Fluorescence titrations and viscosity experiments give convincing evidence for a true intercalative binding of enantiomers with the triplex. However, melting experiments indicated that the two enantiomers selectively stabilized the triplex. The enantiomer ∆-1 stabilize the template duplex and third-strand of the triplex, while it's more effective for stabilization of the template duplex. In stark contrast to ∆-1, Λ-1 stabilizes the triplex without any effect on the third-strand stabilization, suggesting this one extremely prefers to stabilize the template duplex rather than third-strand. Besides, the triplex stabilization effect of ∆-1 is more marked in comparison with that of Λ-1. The obtained results suggest that substituent effects and chiralities of Ru(II) polypyridyl complexes play important roles in the triplex stabilization. Complexes Λ/Δ-[Ru(bpy)2(7-CH3-dppz)]2+ (Λ/Δ-1; bpy = 2,2'-bipyridine, 7-CH3-dppz = 7-methyl-dipyrido[3,2-a,2',3'-c]phenazine) were prepared as stabilizers for poly(U-A ∗ U) triplex. Results suggest the triplex stabilization depends the chiral structures of Λ/Δ-1, indicating that [Ru(bpy)2(7-CH3-dppz)]2+ is a non-specific intercalator for poly(U-A ∗ U) investigated in this work.
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Affiliation(s)
- Zhan Dong
- College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, People's Republic of China. .,Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Xiangtan University, Xiangtan, 411105, People's Republic of China.
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12
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Tan L, Zhang J. A phenolic hydroxyl in the ortho- and meta-positions on the main ligands effect on the interactions of [Ru(phen) 2(o-HPIP)] 2+ and [Ru(phen) 2(m-HPIP)] 2+ with the poly(U)·poly(A)*poly(U) triplex. J Inorg Biochem 2020; 213:111268. [PMID: 33065523 DOI: 10.1016/j.jinorgbio.2020.111268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/23/2020] [Accepted: 09/27/2020] [Indexed: 01/14/2023]
Abstract
The association of two ruthenium(II) complexes [Ru(phen)2(o-HPIP)]2+ (Ru1; phen = 1,10-phenanthroline, o-HPIP = 2-(2-hydroxyphenyl)-imidazo[4,5-f][1,10] phenanthroline) and [Ru(phen)2(m-HPIP)]2+ (Ru2; m-HPIP = 2-(3-hydroxyphenyl)-imidazo[4,5-f][1,10]phenan- throline) with the RNA poly(U)·poly(A)⁎poly(U) triplex has been investigated by spectrophotometric titrations and melting experiments in this work. All experimental data reveal an intercalative triplex-binding mode of the two complexes, whereas the binding constant for Ru1 is significantly higher than that for Ru2. Circular dichroism spectroscopic investigations show that the two complexes could bind to the chiral environment of the triplex, but the triplex perturbation effects induced by Ru1 are more marked. Thermal denaturation experiments demonstrate that both Ru1 and Ru2 display a large binding preference and stabilizing effect for the third strand over the Watson-Crick base-paired duplex of the triplex. However, the third-strand stabilizing effect of Ru1 is much more effective than that of Ru2. The obtained results suggest that positions of the phenolic group on the main ligands have significant effect on the binding of the two complexes with poly(U)·poly(A)⁎poly(U) triplex.
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Affiliation(s)
- Lifeng Tan
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China; Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, People's Republic of China.
| | - Jingwen Zhang
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
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13
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Jiang L, Liu X, Tan L. Synthesis and characterization of chiral Ru(II) polypyridyl complexes and their binding and stabilizing effects toward triple-helical RNA. J Inorg Biochem 2020; 213:111263. [PMID: 33011626 DOI: 10.1016/j.jinorgbio.2020.111263] [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: 07/21/2020] [Revised: 09/10/2020] [Accepted: 09/21/2020] [Indexed: 01/11/2023]
Abstract
Two novel chiral Ru(II) complexes, Λ- and Δ-[Ru(bpy)2(7-CF3-dppz)]2+ (Λ-1 and Δ-1; bpy = 2,2'-bipyridine, 7-CF3-dppz = 7-trifluoromethyl-dipyrido[3,2-a:2',3'-c]phenazine), were synthesized and characterized in this work. The binding and stabilizing effects of Λ-1 and Δ-1 toward the RNA poly(U)•poly(A)*poly(U) triplex were studied by various biophysical techniques. Absorption spectra and fluorescence quenching indicates that the binding affinity of Δ-1 is slightly higher than that Λ-1. Both enantiomers induce significant positive viscosity changes that are indicative of intercalative binding, whereas changes in the relative viscosities of the triplex are found to be more pronounced with Δ-1. Melting experiments indicate that the triplex stabilization effects of both enantiomers are significantly different from each other. With Λ-1, the stabilization of the Watson-Crick base-paired duplex (the template duplex) of the triplex shows a moderate increase, whereas the stabilization of the Hoogsteen base-paired strand (third-strand) exhibits slight decrease under the same conditions, suggesting Λ-1 prefers to stabilize the template duplex rather than third-strand. In stark contrast to Λ-1, Δ-1 can not only strongly stabilize the template duplex, but also moderately increase the third-strand stabilization, even so, which imply that Δ-1 also prefer to stabilize the template duplex instead of the third-strand. These suggest that the [Ru(bpy)2(7-CF3-dppz)]2+ is similar as a non-specific metallointercalator the triplex studied in this work. Combined with our recent research, the obtained results further indicate that Δ- enantiomers rather than Λ-ones of Ru(II) polypyridyl complexes usually exhibit stronger binding and stabilizing effects toward the triplex.
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Affiliation(s)
- Lijuan Jiang
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, People's Republic of China; Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Xiangtan University, Xiangtan 411105, People's Republic of China.
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14
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Jugl A, Pekař M. Hyaluronan-Arginine Interactions-An Ultrasound and ITC Study. Polymers (Basel) 2020; 12:polym12092069. [PMID: 32932626 PMCID: PMC7570013 DOI: 10.3390/polym12092069] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/07/2020] [Accepted: 09/10/2020] [Indexed: 11/16/2022] Open
Abstract
High-resolution ultrasound spectroscopy and isothermal titration calorimetry were used to characterize interactions between hyaluronan and arginine oligomers. The molecular weight of arginine oligomer plays an important role in interactions with hyaluronan. Interactions were observable for arginine oligomers with eight monomer units and longer chains. The effect of the ionic strength and molecular weight of hyaluronan on interactions was tested. In an environment with increased ionic strength, the length of the arginine oligomer was crucial. Generally, sufficiently high ionic strength suppresses interactions between hyaluronan and arginine oligomers, which demonstrated interactions in water. From the point of view of the molecular weight of hyaluronan, the transition between the rod conformation and the random coil conformation appeared to be important.
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15
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Brown JA. Unraveling the structure and biological functions of RNA triple helices. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1598. [PMID: 32441456 PMCID: PMC7583470 DOI: 10.1002/wrna.1598] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 04/06/2020] [Accepted: 04/15/2020] [Indexed: 02/06/2023]
Abstract
It has been nearly 63 years since the first characterization of an RNA triple helix in vitro by Gary Felsenfeld, David Davies, and Alexander Rich. An RNA triple helix consists of three strands: A Watson–Crick RNA double helix whose major‐groove establishes hydrogen bonds with the so‐called “third strand”. In the past 15 years, it has been recognized that these major‐groove RNA triple helices, like single‐stranded and double‐stranded RNA, also mediate prominent biological roles inside cells. Thus far, these triple helices are known to mediate catalysis during telomere synthesis and RNA splicing, bind to ligands and ions so that metabolite‐sensing riboswitches can regulate gene expression, and provide a clever strategy to protect the 3′ end of RNA from degradation. Because RNA triple helices play important roles in biology, there is a renewed interest in better understanding the fundamental properties of RNA triple helices and developing methods for their high‐throughput discovery. This review provides an overview of the fundamental biochemical and structural properties of major‐groove RNA triple helices, summarizes the structure and function of naturally occurring RNA triple helices, and describes prospective strategies to isolate RNA triple helices as a means to establish the “triplexome”. This article is categorized under:RNA Structure and Dynamics > RNA Structure and Dynamics RNA Structure and Dynamics > RNA Structure, Dynamics and Chemistry RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems
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Affiliation(s)
- Jessica A Brown
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
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16
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Del Mundo IMA, Vasquez KM, Wang G. Modulation of DNA structure formation using small molecules. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2019; 1866:118539. [PMID: 31491448 PMCID: PMC6851491 DOI: 10.1016/j.bbamcr.2019.118539] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 08/20/2019] [Accepted: 08/24/2019] [Indexed: 02/06/2023]
Abstract
Genome integrity is essential for proper cell function such that genetic instability can result in cellular dysfunction and disease. Mutations in the human genome are not random, and occur more frequently at "hotspot" regions that often co-localize with sequences that have the capacity to adopt alternative (i.e. non-B) DNA structures. Non-B DNA-forming sequences are mutagenic, can stimulate the formation of DNA double-strand breaks, and are highly enriched at mutation hotspots in human cancer genomes. Thus, small molecules that can modulate the conformations of these structure-forming sequences may prove beneficial in the prevention and/or treatment of genetic diseases. Further, the development of molecular probes to interrogate the roles of non-B DNA structures in modulating DNA function, such as genetic instability in cancer etiology are warranted. Here, we discuss reported non-B DNA stabilizers, destabilizers, and probes, recent assays to identify ligands, and the potential biological applications of these DNA structure-modulating molecules.
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Affiliation(s)
- Imee M A Del Mundo
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Dell Pediatric Research Institute, 1400 Barbara Jordan Blvd., Austin, TX 78723, USA
| | - Karen M Vasquez
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Dell Pediatric Research Institute, 1400 Barbara Jordan Blvd., Austin, TX 78723, USA.
| | - Guliang Wang
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Dell Pediatric Research Institute, 1400 Barbara Jordan Blvd., Austin, TX 78723, USA
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17
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Akula SM, Candido S, Libra M, Abrams SL, Steelman LS, Lertpiriyapong K, Ramazzotti G, Ratti S, Follo MY, Martelli AM, Murata RM, Rosalen PL, Bueno-Silva B, Matias de Alencar S, Montalto G, Cervello M, Gizak A, Rakus D, Mao W, Lin HL, Lombardi P, McCubrey JA. Abilities of berberine and chemically modified berberines to interact with metformin and inhibit proliferation of pancreatic cancer cells. Adv Biol Regul 2019; 73:100633. [PMID: 31047842 DOI: 10.1016/j.jbior.2019.04.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/11/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
Pancreatic cancer is devastating cancer worldwide with few if any truly effective therapies. Pancreatic cancer has an increasing incidence and may become the second leading cause of death from cancer. Novel, more effective therapeutic approaches are needed as pancreatic cancer patients usually survive for less than a year after being diagnosed. Control of blood sugar levels by the prescription drug metformin in diseases such as diabetes mellitus has been examined in association with pancreatic cancer. While the clinical trials remain inconclusive, there is hope that certain diets and medications may affect positively the outcomes of patients with pancreatic and other cancers. Other natural compounds may share some of the effects of metformin. One "medicinal" fruit consumed by millions worldwide is berberine (BBR). Metformin and BBR both activate AMP-activated protein kinase (AMPK) which is a key mediator of glucose metabolism. Glucose metabolism has been shown to be very important in cancer and its significance is increasing. In the following studies, we have examined the effects of metformin, BBR and a panel of modified BBRs (NAX compounds) and chemotherapeutic drugs on the growth of four different human pancreatic adenocarcinoma cell lines (PDAC). Interestingly, the effects of metformin could be enhanced by BBR and certain modified BBRs. Upon restoration of WT-TP53 activity in MIA-PaCa-2 cells, an altered sensitivity to the combination of certain NAX compounds and metformin was observed compared to the parental cells which normally lack WT-TP53. Certain NAX compounds may interact with WT-TP53 and metformin treatment to alter the expression of key molecules involved in cell growth. These results suggest a therapeutic approach by combining certain pharmaceutical drugs and nutraceuticals to suppress the growth of cancer cells.
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Affiliation(s)
- Shaw M Akula
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA.
| | - Saverio Candido
- Department of Biomedical and Biotechnological Sciences - Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy; Research Center for Prevention, Diagnosis and Treatment of Cancer (PreDiCT), University of Catania, Catania, Italy
| | - Massimo Libra
- Department of Biomedical and Biotechnological Sciences - Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy; Research Center for Prevention, Diagnosis and Treatment of Cancer (PreDiCT), University of Catania, Catania, Italy
| | - Stephen L Abrams
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Linda S Steelman
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Kvin Lertpiriyapong
- Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medicine and the Hospital for Special Surgery, New York City, New York, USA
| | - Giulia Ramazzotti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Stefano Ratti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Matilde Y Follo
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Alberto M Martelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Ramiro M Murata
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA; Department of Foundational Sciences, School of Dental Medicine, East Carolina University, USA
| | - Pedro L Rosalen
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - Bruno Bueno-Silva
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil; Dental Research Division, Guarulhos University, Guarulhos, Brazil
| | | | - Giuseppe Montalto
- Dipartimento di Promozione Della Salute, Materno-Infantile, Medicina Interna e Specialistica di Eccellenza (PROMISE), University of Palermo, Palermo, Italy; Consiglio Nazionale Delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Melchiorre Cervello
- Consiglio Nazionale Delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Agnieszka Gizak
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Dariusz Rakus
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Weifeng Mao
- College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Heng-Liang Lin
- Catholic Fu Jen University Hospital, New Taipei City, Taiwan
| | - Paolo Lombardi
- Naxospharma, Via Giuseppe di Vittorio 70, Novate Milanese, 20026, Italy
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA.
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Tan Z, Zhu J, Ni W, Liu X, Li Y, Tan L. Binding properties of two ruthenium(II) polypyridyl complexes [Ru(bpy) 2(dppz-Br)] 2+ and [Ru(dmb) 2(dppz-Br)] 2+ with the RNA poly(U)•poly(A)*poly(U) triplex. J Biol Inorg Chem 2019; 24:721-731. [PMID: 31312912 DOI: 10.1007/s00775-019-01685-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 07/08/2019] [Indexed: 01/14/2023]
Abstract
Two ruthenium(II) polypyridyl complexes containing different ancillary ligands, [Ru(bpy)2(dppz-Br)]2+ (Ru1; bpy = 2,2'-bipyridine dppz-Br = 7-Br-dipyrido[3,2-a,2',3'-c]-phenazine) and [Ru(dmb)2(dppz-Br)]2+ (Ru2; dmb = 4,4'-dimethyl-2,2'-bipyridine), have been synthesized and characterized. Binding properties of Ru1 and Ru2 with the RNA poly(U)•poly(A)*poly(U) triplex have been investigated by UV-Vis spectroscopy, fluorescence spectroscopy, viscosity measurements as well as circular dichroism and thermal denaturation. Spectrophotometric studies together with viscosity measurements suggest that both Ru1 and Ru2 bind with the triplex by intercalation mode, and the melting experiments demonstrate that the two complexes can effectively enhance the triplex stabilization. However, results indicate that Ru1 stabilizes the third-strand and Watson-Crick base-paired duplex of the triplex without obvious selectivity. In contrast, Ru2 prefers to bind with the third strand rather than the Watson-Crick base-paired duplex of the triplex to a some extent under the same conditions used in this study, thereby significantly stabilizing the third strand. The obtained results of this study suggest that slight differences in the ancillary ligands bpy and dmb should be the main factor affecting the binding interactions of the two complexes with the triplex.
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Affiliation(s)
- Zanru Tan
- College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Juan Zhu
- College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Wen Ni
- College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan, 411105, People's Republic of China
| | - Yi Li
- Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, 411201, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, 411105, People's Republic of China. .,Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Xiangtan University, Xiangtan, 411105, People's Republic of China.
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19
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Wang F, Sun Y, Liu X, Li Y, Tan L. Third-strand stabilizing effects of the RNA poly(U)·poly(A)*poly(U) triplex by a ruthenium(II) polypyridine complex and its hexaarginine peptide conjugate. Int J Biol Macromol 2019; 135:1134-1141. [PMID: 31176864 DOI: 10.1016/j.ijbiomac.2019.06.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/28/2019] [Accepted: 06/04/2019] [Indexed: 01/14/2023]
Abstract
In this work, a Ru(II) complex [Ru(bpy)2(pip-CO2H)]2+ (Ru1) and its hexaarginine peptide conjugate [Ru(bpy)2(pic-Arg6)]8+ (Ru2) have been synthesized and characterized. The binding of Ru1 and Ru2 with poly(U)•poly(A)*poly(U) triplex has been studied. Results suggest that Ru1 binds in the surface of the minor groove while Ru2 binds to the minor groove of the triplex. Consequently, the triplex stabilization is barely affected by Ru1, while with Ru2 the triplex stabilizing effect is so strong that that dissociation of the triplex shows an overlapping of both melting processes with the melting temperature increased to a maximum of 56.1 °C at the CRu2/CUAU ratio of 0.05, where ΔTm1 and ΔTm2 are 19.6 and 10.1 °C, respectively. Furthermore, the effect of Ru2 stabilizing the third strand at such a low binding ratio of 0.05 is more marked than what obsereved for flavone luteolin and [Ru(bpy)2(mdpz)]2+, which are so far the strongest triplex stabilizers in the reported organic small molecules and metal complexes, respectively. Considering the structure natures of Ru2, conceivably except for electrostatic interaction, the forces stabilizing the triplex should also involve hydrophobic interaction and hydrogen bingding. To our knowledge, this work represents a first example of improving the triplex stabilization by a metallopeptide.
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Affiliation(s)
- Fangfang Wang
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Yanmei Sun
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Xiaohua Liu
- Academic Affairs Office, Xiangtan University, Xiangtan 411105, PR China
| | - Yi Li
- Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, PR China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, PR China; Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Xiangtan University, Xiangtan 411105, PR China.
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20
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Wang F, Ma S, Feng Y, Liu X, Tan L. Binding propterties of two Ru(II) polypyridyl complexes containing dppz units and fluorine groups with poly(U)·poly(A) ∗ poly(U) triplex. J Inorg Biochem 2019; 197:110705. [PMID: 31071642 DOI: 10.1016/j.jinorgbio.2019.110705] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 04/26/2019] [Accepted: 05/01/2019] [Indexed: 01/14/2023]
Abstract
In this work, two Ru(II)-dppz (dppz = dipyrido[3,2-a:2',3'-c]phenazine) complexes containing fluorine substituents, [Ru(bpy)2(7-F-dppz)]2+ (Ru1, bpy = 2,2'-bipyridine, 7-F-dppz = 7-fluorodipyrido[3,2-a:2',3'-c]phenazine) and [Ru(phen)2(7-F-dppz)]2+ (Ru2, phen = 1,10-phenanthroline), have been synthesized and characterized. Binding properties of Ru1 and Ru2 with the RNA poly(U)·poly(A) ∗ poly(U) triplex have been studied by spectroscopic methods and viscosity measurements. The obtained results indicate that the binding differences of the two complexes with the triplex may be attributed to the ancillary ligand effects, implying that the better planarity and greater hydrophobicity of ancillary ligands are advantageous to the π-π stacking interaction between Ru2 and the triplex, thus Ru2 stabilizes the triplex strongly than Ru1. Denaturation of the triplex shows that both Ru1 and Ru2 can not only highly stabilize the template duplex of the triplex, but also significantly stabilize the third strand. Compared with the triplex stabilizing effects for the reported Ru(II)-dppz complexes, thermal melting experiments suggest that the fluorine substituent on the ligand dppz can probably decrease electrostatic repulsion between the three strands of the triplex, thereby Ru1 and Ru2 significantly increase the triplex stabilization. Results obtained from this work further confirm that the substituent electron effect of dppz-based ligands and the planarity and hydrophobicity of ancillary ligands play an important role in the triplex stabilizing effects by Ru(II)-dppz complexes.
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Affiliation(s)
- Fangfang Wang
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Shuai Ma
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Yongdeng Feng
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Xiaohua Liu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, People's Republic of China; Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Xiangtan University, Xiangtan 411105, People's Republic of China.
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21
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Feng Y, Liu X, Ma S, Wang F, Tan L. Ruthenium(II) polypyridyl complex [Ru(phen) 2dppz-idzo] 2+ as a colorimetric molecular "light switch" and powerful stabilizer for the RNA triplex poly(U)·poly(A)*poly(U). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 212:240-245. [PMID: 30641364 DOI: 10.1016/j.saa.2018.12.048] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/09/2018] [Accepted: 12/27/2018] [Indexed: 06/09/2023]
Abstract
The interaction of [Ru(phen)2dppz-idzo]2+ (phen = 1,10-phenanthroline, dppz-idzo = dppz-imidazolone) with triplex RNA poly(U)·poly(A)*poly(U) was carried out by using spectroscopic and viscometric techniques in this work. Luminescent titrations suggest that [Ru(phen)2dppz-idzo]2+ shows better selectivity for poly(U)·poly(A)*poly(U) compared with poly(U)·poly(A) and poly(U), this complex exhibits a "light switch" effect with an emission enhancement factor of about 123 in the presence of poly(U)·poly(A)*poly(U). Significantly, this "light switch" behavior could even be observed by the naked eye under irradiation with UV light. To our knowledge, [Ru(bpy)2dppz-idzo]2+ is the first small molecule able to serve as a colorimetric molecular "light switch" for the triplex poly(U)·poly(A)*poly(U). Combined with the spectral and viscometric results as well as [Ru(phen)2dppz-idzo]2+ stabilizing the template duplex poly(U)·poly(A), we speculate that [Ru(phen)2dppz-idzo]2+ prefers to bind with the Hoogsteen base-paired strand (the third strand) of the triplex, thus the intercalating [Ru(phen)2dppz-idzo]2+ stabilizing the third strand is more marked in comparison with the Watson-Crick base-paired duplex of the triplex. The results obtained here may be useful for understanding the interaction of triplex RNA poly(U)·poly(A)*poly(U) with small molecule, particularly ruthenium(II) complexes.
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Affiliation(s)
- Yongdeng Feng
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Xiaohua Liu
- School of Chemical Engineering, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Shuai Ma
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Fangfang Wang
- College of Chemistry, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, People's Republic of China.
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Ma S, Wang F, Feng Y, Liu X, Tan L. Binding properties of ruthenium(II) complexes [Ru(phen)2(dicnq)]2+ and [Ru(bpy)2(dicnq)]2+ with the RNA triplex poly(U)·poly(A)*poly(U). Polyhedron 2019. [DOI: 10.1016/j.poly.2019.01.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abrams SL, Follo MY, Steelman LS, Lertpiriyapong K, Cocco L, Ratti S, Martelli AM, Candido S, Libra M, Murata RM, Rosalen PL, Montalto G, Cervello M, Gizak A, Rakus D, Mao W, Lombardi P, McCubrey JA. Abilities of berberine and chemically modified berberines to inhibit proliferation of pancreatic cancer cells. Adv Biol Regul 2019; 71:172-182. [PMID: 30361003 DOI: 10.1016/j.jbior.2018.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 10/15/2018] [Accepted: 10/16/2018] [Indexed: 06/08/2023]
Abstract
Berberine (BBR) is a common nutraceutical consumed by millions worldwide. BBR has many different effects on human health, e.g., diabetes, diarrhea, inflammation and now more recently it has been proposed to have potent anti-cancer effects. BBR has been shown to suppress the growth of cancer cells more than normal cells. BBR has been proposed to exert its growth-inhibitory effects by many different biochemical mechanisms including: suppression of cell cycle progression, induction of reactive oxygen species, induction of apoptosis and autophagy and interactions with DNA potentially leading to DNA damage, and altered gene expression. Pancreatic cancer is a leading cancer worldwide associated with a poor prognosis. As our population ages, pancreatic cancer has an increasing incidence and will likely become the second leading cause of death from cancer. There are few truly-effective therapeutic options for pancreatic cancer. Surgery and certain chemotherapeutic drugs are used to treat pancreatic cancer patients. Novel approaches to treat pancreatic cancer patients are direly needed as they usually survive for less than a year after being diagnosed. In the following manuscript, we discuss the abilities of BBR and certain chemically-modified BBRs (NAX compounds) to suppress growth of pancreatic cancer cells.
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Affiliation(s)
- Stephen L Abrams
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Matilde Y Follo
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Linda S Steelman
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Kvin Lertpiriyapong
- Department of Comparative Medicine, Brody School of Medicine at East Carolina University, USA; Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medicine and the Hospital for Special Surgery, New York City, NY, USA
| | - Lucio Cocco
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Stefano Ratti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Alberto M Martelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Saverio Candido
- Department of Biomedical and Biotechnological Sciences - Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Massimo Libra
- Department of Biomedical and Biotechnological Sciences - Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Ramiro M Murata
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA; Department of Foundational Sciences, School of Dental Medicine, East Carolina University, USA
| | - Pedro L Rosalen
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - Giuseppe Montalto
- Biomedical Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy; Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Melchiorre Cervello
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Agnieszka Gizak
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Dariusz Rakus
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Weifeng Mao
- College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning, China
| | - Paolo Lombardi
- Naxospharma, Via Giuseppe di Vittorio 70, Novate Milanese, 20026, Italy
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA.
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Basu A, Kumar GS. Nucleic acids binding strategies of small molecules: Lessons from alkaloids. Biochim Biophys Acta Gen Subj 2018; 1862:1995-2016. [DOI: 10.1016/j.bbagen.2018.06.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/11/2018] [Accepted: 06/11/2018] [Indexed: 01/14/2023]
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Hesari A, Ghasemi F, Cicero AFG, Mohajeri M, Rezaei O, Hayat SMG, Sahebkar A. Berberine: A potential adjunct for the treatment of gastrointestinal cancers? J Cell Biochem 2018; 119:9655-9663. [DOI: 10.1002/jcb.27392] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/09/2018] [Indexed: 12/14/2022]
Affiliation(s)
- AmirReza Hesari
- Department of Biotechnology Faculty of Medicine, Arak University of Medical Sciences Arak Iran
| | - Faezeh Ghasemi
- Department of Biotechnology Faculty of Medicine, Arak University of Medical Sciences Arak Iran
| | - Arrigo F. G. Cicero
- Medical and Surgical Sciences Department University of Bologna Bologna Italy
| | - Mohammad Mohajeri
- Neurogenic Inflammation Research Center Mashhad University of Medical Sciences Mashhad Iran
- Department of Medical Biotechnology Faculty of Medicine, Mashhad University of Medical Sciences Mashhad Iran
| | - Omid Rezaei
- Faculty of Medicine, Arak University of Medical Sciences Arak Iran
| | | | - Amirhossein Sahebkar
- Neurogenic Inflammation Research Center Mashhad University of Medical Sciences Mashhad Iran
- Biotechnology Research Center, Pharmaceutical Technology Institute Mashhad University of Medical Sciences Mashhad Iran
- School of Pharmacy Mashhad University of Medical Sciences Mashhad Iran
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Carr CE, Khutsishvili I, Marky LA. Energetics, Ion, and Water Binding of the Unfolding of AA/UU Base Pair Stacks and UAU/UAU Base Triplet Stacks in RNA. J Phys Chem B 2018; 122:7057-7065. [PMID: 29932334 DOI: 10.1021/acs.jpcb.8b05575] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Triplex formation occurs via interaction of a third strand with the major groove of double-stranded nucleic acid, through Hoogsteen hydrogen bonding. In this work, we use a combination of temperature-dependent UV spectroscopy and differential scanning calorimetry to determine complete thermodynamic profiles for the unfolding of polyadenylic acid (poly(rA))·polyuridylic acid (poly(rU)) (duplex) and poly(rA)·2poly(rU) (triplex). Our thermodynamic results are in good agreement with the much earlier work of Krakauer and Sturtevant using only UV melting techniques. The folding of these two helices yielded an uptake of ions, Δ nNa+ = 0.15 mol Na+/mol base pair (duplex) and 0.30 mol Na+/mole base triplet (triplex), which are consistent with their polymer behavior and the higher charge density parameter of triple helices. The osmotic stress technique yielded a release of structural water, Δ nW = 2 mol H2O/mol base pair (duplex unfolding into single strands) and an uptake of structural water, Δ nW = 2 mol H2O/mole base pair (triplex unfolding into duplex and a single strand). However, an overall release of electrostricted waters is obtained for the unfolding of both complexes from pressure perturbation calorimetric experiments. In total, the Δ V values obtained for the unfolding of triplex into duplex and a single strand correspond to an immobilization of two structural waters and a release of three electrostricted waters. The Δ V values obtained for the unfolding of duplex into two single strands correspond to the release of two structural waters and the immobilization of four electrostricted water molecules.
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Affiliation(s)
- Carolyn E Carr
- Department of Pharmaceutical Sciences , University of Nebraska Medical Center , 986025 Nebraska Medical Center , Omaha , Nebraska 68198-6025 , United States
| | - Irine Khutsishvili
- Department of Pharmaceutical Sciences , University of Nebraska Medical Center , 986025 Nebraska Medical Center , Omaha , Nebraska 68198-6025 , United States
| | - Luis A Marky
- Department of Pharmaceutical Sciences , University of Nebraska Medical Center , 986025 Nebraska Medical Center , Omaha , Nebraska 68198-6025 , United States
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Binding properties of chiral ruthenium(II) complexes Λ- and Δ-[Ru(bpy) 2dppz-11-CO 2Me] 2+ toward the triplex RNA poly(U)•poly(A)*poly(U). J Inorg Biochem 2018; 186:51-59. [PMID: 29852349 DOI: 10.1016/j.jinorgbio.2018.05.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/20/2018] [Accepted: 05/22/2018] [Indexed: 12/29/2022]
Abstract
Two chiral ruthenium(II) complexes containing ligand dppz-CO2Me (dppz-11-CO2Me = dipyrido[3,2-a,2',3'-c]phenazine-11-carboxylic acid methyl ester), Δ-[Ru(bpy)2dppz-11-CO2Me]2+ (bpy = 2,2'-bipyridine; Δ-1) and Λ-[Ru(bpy)2dppz-11-CO2Me]2+ (Λ-1), were synthesized and characterized. The binding of the two enantiomers with the triplex RNA poly(U)•poly(A)*poly(U) was carried out by various biophysical techniques. Analysis of the absorption and fluorescence features indicates that the binding strengths of the two enantiomers toward the triplex RNA differ only slightly from each other. The total increase in viscosity and shape of the curves for the triplex RNA with Λ-1 is similar to that with Δ-1, suggesting the binding modes of two enantiomers with the triplex RNA are intercalation. Thermal melting measurements indicate that the stabilization effects clearly depended on the concentrations of Λ-1 and Δ-1. However, the third-strand stabilizing effect of Δ-1 dramatically differs from that of Λ-1 when they interact with the chiral environment of the RNA triple at pH = 7.0 and [Na+] = 35 mM. Combined with the CD (CD = circular dichroism) variations of the triplex RNA with either Λ-1 or Δ-1, the reason for their different triplex stabilization effects may originate from the two enantiomers through different orientations intercalating into nucleobases of the triplex. In addition, effects of higher ionic strengths on the triplex stabilization in the absence and presence of the two enantiomers have also been studied. The results presented here may be useful for understanding the binding properties of the triplex RNA with small molecule, particularly chiral ruthenium(II) complexes.
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Candido S, Abrams SL, Steelman L, Lertpiriyapong K, Martelli AM, Cocco L, Ratti S, Follo MY, Murata RM, Rosalen PL, Lombardi P, Montalto G, Cervello M, Gizak A, Rakus D, Suh PG, Libra M, McCubrey JA. Metformin influences drug sensitivity in pancreatic cancer cells. Adv Biol Regul 2018; 68:13-30. [PMID: 29482945 DOI: 10.1016/j.jbior.2018.02.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/03/2018] [Accepted: 02/05/2018] [Indexed: 06/08/2023]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive, highly metastatic malignancy and accounts for 85% of pancreatic cancers. PDAC patients have poor prognosis with a five-year survival of only 5-10% after diagnosis and treatment. Pancreatic cancer has been associated with type II diabetes as the frequency of recently diagnosed diabetics that develop pancreatic cancer within a 10-year period of initial diagnosis of diabetes in increased in comparison to non-diabetic patients. Metformin is a very frequently prescribed drug used to treat type II diabetes. Metformin acts in part by stimulating AMP-kinase (AMPK) and results in the suppression of mTORC1 activity and the induction of autophagy. In the following studies, we have examined the effects of metformin in the presence of various chemotherapeutic drugs, signal transduction inhibitors and natural products on the growth of three different PDAC lines. Metformin, by itself, was not effective at suppressing growth of the pancreatic cancer cell lines at concentration less than 1000 nM, however, in certain PDAC lines, a suboptimal dose of metformin (250 nM) potentiated the effects of various chemotherapeutic drugs used to treat pancreatic cancer (e.g., gemcitabine, cisplatin, 5-fluorouracil) and other cancer types (e.g., doxorubicin, docetaxel). Furthermore, metformin could increase anti-proliferative effects of mTORC1 and PI3K/mTOR inhibitors as well as natural products such as berberine and the anti-malarial drug chloroquine in certain PDAC lines. Thus, metformin can enhance the effects of certain drugs and signal transduction inhibitors which are used to treat pancreatic and various other cancers.
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Affiliation(s)
- Saverio Candido
- Department of Biomedical and Biotechnological Sciences - Pathology & Oncology Section, University of Catania, Catania, Italy
| | - Stephen L Abrams
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Linda Steelman
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Kvin Lertpiriyapong
- Department of Comparative Medicine, Brody School of Medicine at East Carolina University, USA
| | - Alberto M Martelli
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, Bologna, Italy
| | - Lucio Cocco
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, Bologna, Italy
| | - Stefano Ratti
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, Bologna, Italy
| | - Matilde Y Follo
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, Bologna, Italy
| | - Ramiro M Murata
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA; Department of Foundational Sciences, School of Dental Medicine, East Carolina University, USA
| | - Pedro L Rosalen
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - Paolo Lombardi
- Naxospharma, Via Giuseppe Di Vittorio 70, Novate Milanese 20026, Italy
| | - Giuseppe Montalto
- Biomedical Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy; Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Melchiorre Cervello
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Agnieszka Gizak
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Dariusz Rakus
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Pann-Gill Suh
- School of Life Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Massimo Libra
- Department of Biomedical and Biotechnological Sciences - Pathology & Oncology Section, University of Catania, Catania, Italy
| | - James A McCubrey
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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McCubrey JA, Lertpiriyapong K, Steelman LS, Abrams SL, Yang LV, Murata RM, Rosalen PL, Scalisi A, Neri LM, Cocco L, Ratti S, Martelli AM, Laidler P, Dulińska-Litewka J, Rakus D, Gizak A, Lombardi P, Nicoletti F, Candido S, Libra M, Montalto G, Cervello M. Effects of resveratrol, curcumin, berberine and other nutraceuticals on aging, cancer development, cancer stem cells and microRNAs. Aging (Albany NY) 2018; 9:1477-1536. [PMID: 28611316 PMCID: PMC5509453 DOI: 10.18632/aging.101250] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 06/04/2017] [Indexed: 02/07/2023]
Abstract
Natural products or nutraceuticals have been shown to elicit anti-aging, anti-cancer and other health-enhancing effects. A key target of the effects of natural products may be the regulation of microRNA (miR) expression which results in cell death or prevents aging, diabetes, cardiovascular and other diseases. This review will focus on a few natural products, especially on resveratrol (RES), curcumin (CUR) and berberine (BBR). RES is obtained from the skins of grapes and other fruits and berries. RES may extend human lifespan by activating the sirtuins and SIRT1 molecules. CUR is isolated from the root of turmeric (Curcuma longa). CUR is currently used in the treatment of many disorders, especially in those involving an inflammatory process. CUR and modified derivatives have been shown to have potent anti-cancer effects, especially on cancer stem cells (CSC). BBR is also isolated from various plants (e.g., Coptis chinensis) and has been used for centuries in traditional medicine to treat diseases such as adult- onset diabetes. Understanding the benefits of these and other nutraceuticals may result in approaches to improve human health.
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Affiliation(s)
- James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
| | - Kvin Lertpiriyapong
- Department of Comparative Medicine, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
| | - Linda S Steelman
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
| | - Steve L Abrams
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
| | - Li V Yang
- Department of Internal Medicine, Hematology/Oncology Section, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
| | - Ramiro M Murata
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA.,Department of Foundational Sciences, School of Dental Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Pedro L Rosalen
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - Aurora Scalisi
- Unit of Oncologic Diseases, ASP-Catania, Catania 95100, Italy
| | - Luca M Neri
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Lucio Cocco
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Stefano Ratti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Alberto M Martelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Piotr Laidler
- Chair of Medical Biochemistry, Jagiellonian University Medical College, Kraków, Poland
| | | | - Dariusz Rakus
- Department of Animal Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Agnieszka Gizak
- Department of Animal Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | | | - Ferdinando Nicoletti
- Department of Biomedical and Biotechnological Sciences, Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Saverio Candido
- Department of Biomedical and Biotechnological Sciences, Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Massimo Libra
- Department of Biomedical and Biotechnological Sciences, Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Giuseppe Montalto
- Biomedical Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy.,Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Melchiorre Cervello
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
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Haque L, Bhuiya S, Das S. Self-structure assembly in single stranded polyriboadenylic acid by benzophenanthridine alkaloid: Spectroscopic and calorimetric exploration. Int J Biol Macromol 2018; 106:1130-1138. [DOI: 10.1016/j.ijbiomac.2017.08.119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 08/19/2017] [Accepted: 08/21/2017] [Indexed: 02/07/2023]
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31
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McCubrey JA, Abrams SL, Lertpiriyapong K, Cocco L, Ratti S, Martelli AM, Candido S, Libra M, Murata RM, Rosalen PL, Lombardi P, Montalto G, Cervello M, Gizak A, Rakus D, Steelman LS. Effects of berberine, curcumin, resveratrol alone and in combination with chemotherapeutic drugs and signal transduction inhibitors on cancer cells-Power of nutraceuticals. Adv Biol Regul 2018; 67:190-211. [PMID: 28988970 DOI: 10.1016/j.jbior.2017.09.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 09/29/2017] [Indexed: 06/07/2023]
Abstract
Over the past fifty years, society has become aware of the importance of a healthy diet in terms of human fitness and longevity. More recently, the concept of the beneficial effects of certain components of our diet and other compounds, that are consumed often by different cultures in various parts of the world, has become apparent. These "healthy" components of our diet are often referred to as nutraceuticals and they can prevent/suppress: aging, bacterial, fungal and viral infections, diabetes, inflammation, metabolic disorders and cardiovascular diseases and have other health-enhancing effects. Moreover, they are now often being investigated because of their anti-cancer properties/potentials. Understanding the effects of various natural products on cancer cells may enhance their usage as anti-proliferative agents which may be beneficial for many health problems. In this manuscript, we discuss and demonstrate how certain nutraceuticals may enhance other anti-cancer drugs to suppress proliferation of cancer cells.
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Affiliation(s)
- James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA.
| | - Stephen L Abrams
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
| | - Kvin Lertpiriyapong
- Department of Comparative Medicine, Brody School of Medicine at East Carolina University, USA; Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medicine and the Hospital for Special Surgery, New York City, New York, USA
| | - Lucio Cocco
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Stefano Ratti
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Alberto M Martelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Saverio Candido
- Department of Biomedical and Biotechnological Sciences - Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Massimo Libra
- Department of Biomedical and Biotechnological Sciences - Oncological, Clinical and General Pathology Section, University of Catania, Catania, Italy
| | - Ramiro M Murata
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA; Department of Foundational Sciences, School of Dental Medicine, East Carolina University, USA
| | - Pedro L Rosalen
- Department of Physiological Sciences, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil
| | - Paolo Lombardi
- Naxospharma, Via Giuseppe Di Vittorio 70, Novate Milanese 20026, Italy
| | - Giuseppe Montalto
- Biomedical Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy; Consiglio Nazionale Delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Melchiorre Cervello
- Consiglio Nazionale Delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Palermo, Italy
| | - Agnieszka Gizak
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Dariusz Rakus
- Department of Molecular Physiology and Neurobiology, Wroclaw University, Wroclaw, Poland
| | - Linda S Steelman
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA
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32
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Peng M, Ni W, Tan L. Effects of the fluorine substituent positions of the intercalating ligands on the binding behavior and third-strand stabilization of two Ru(II) complexes toward poly(U)•poly(A)*poly(U) triplex RNA. J Inorg Biochem 2017; 175:276-283. [PMID: 28806644 DOI: 10.1016/j.jinorgbio.2017.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 07/10/2017] [Accepted: 08/05/2017] [Indexed: 01/03/2023]
Abstract
Two new Ru(II) polypyridyl complexes containing fluorine substituents, [Ru(bpy)2(o-fpip)]2+ (Ru1, bpy=2,2'-bipyridine, o-fpip=2-(2-fluorophenyl)imidazo[4,5-f] [1,10]phenanthroline) and [Ru(bpy)2(p-fpip)]2+ (Ru2, p-fpip=2-(4-fluorophenyl)imidazo[4,5-f] [1,10]phenanthroline) have been synthesized as binders for poly(U)•poly(A)∗poly(U) triplex RNA. The binding of the two complexes with the triplex RNA has been investigated by spectroscopic methods and viscosity measurements. Analysis of the electronic absorption spectra indicates that the association of intercalating Ru2 with the triplex RNA is greater than that of Ru1, which is also supported by spectroscopic titrations and viscosity measurements. Thermal denaturation studies reflect that third-strand stabilization depend on the nature of the two complexes and Ru2 is more effective for stabilization of the triplex RNA. Circular dichroism spectra of the triplex RNA in the presence of metal complexes indicate that the binding-induced CD perturbation of the triplex structure is more obvious by Ru2. The main results obtained here suggest that the positions of fluorine substituent in the intercalating ligands have a significant effect on the two complexes stabilizing the third strand.
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Affiliation(s)
- Mengna Peng
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Wen Ni
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, PR China.
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33
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Tang W, Zhu Z, Tan L. [Ru(bpy)2(7-CH3-dppz)](2+) and [Ru(phen)2(7-CH3-dppz)](2+) as metallointercalators that affect third-strand stabilization of the poly(U)˙poly(A)*poly(U) triplex. MOLECULAR BIOSYSTEMS 2017; 12:1478-85. [PMID: 26999574 DOI: 10.1039/c6mb00094k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stable RNA triplexes play key roles in many biological processes. However, due to Hoogsteen base pairing, triplexes are thermodynamically less stable than the corresponding duplexes. To understand the factors effecting the stabilization of RNA triplexes by octahedral ruthenium(ii) complexes, two Ru(ii) complexes, [Ru(bpy)2(7-CH3-dppz)](2+) (Ru) and [Ru(phen)2(7-CH3-dppz)](2+) (Ru), have been synthesized and characterized in this work. The interactions of the two Ru(ii) complexes with the poly(U)˙poly(A)*poly(U) triplex are investigated by spectrophotometry, spectrofluorometry, circular dichroism as well as viscometry. The results demonstrate that the two complexes are able to enhance the stability of the RNA triplex and serve as molecular "light switches" for the triplex. However, Ru and Ru affecting the stabilization of the third strand are significantly weaker than that of the Watson-Crick base-paired duplex, suggesting that the binding of the two complexes with the triplex is favored by the Watson-Crick base-paired duplex to a large extent. In addition, considering the nature of Ru and Ru, we presume that their binding differences may be due to different ancillary ligand effects. This study further advances our knowledge on the interaction of RNA triple-stranded structures with metal complexes, particularly with Ru(ii) complexes.
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Affiliation(s)
- Wuzhi Tang
- College of Chemistry, Xiangtan University, Xiangtan 411105, P. R. China.
| | - Zhiyuan Zhu
- College of Chemistry, Xiangtan University, Xiangtan 411105, P. R. China.
| | - Lifeng Tan
- College of Chemistry, Xiangtan University, Xiangtan 411105, P. R. China. and Key Lab of Environmentally Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, P. R. China
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34
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Basu P, Suresh Kumar G. Small molecule-RNA recognition: Binding of the benzophenanthridine alkaloids sanguinarine and chelerythrine to single stranded polyribonucleotides. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2017; 174:173-181. [PMID: 28779690 DOI: 10.1016/j.jphotobiol.2017.07.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/18/2017] [Accepted: 07/21/2017] [Indexed: 01/18/2023]
Abstract
Single stranded RNAs are biologically potent as they participate in various key cellular processes. The binding efficacy of two potent anticancer alkaloids, sanguinarine (here after SANG) and chelerythrine (here after CHEL), with single-stranded ribonucleic acids poly(rI), poly(rG), and poly(rC) were studied using spectroscopic and thermodynamic tools. Results reveal that both SANG and CHEL binds well with single stranded RNAs with affinity in the order poly(rI)>poly(rG)>poly(rC). CHEL showed slightly higher affinity compared to SANG with all the single stranded RNAs. Both SANG and CHEL showed association affinity of the lower 106 order with poly(rI), higher 105 order binding with poly(rG) and lower 105 order with poly(rC). The binding mode was partial intercalation due to the staking interaction between the bases and the alkaloids. The complexation of both the SANG and CHEL to the RNAs were mainly enthalpy driven and also favoured by entropy changes. Perturbation was observed in the RNA conformation due to binding of the alkaloids. In this present study we have deciphered the fundamental structural and calorimetric aspects of the interaction of the natural benzophenanthridine alkaloids with single stranded RNAs and these results may help to develop new generation alkaloid based therapeutics targeting single stranded RNAs.
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Affiliation(s)
- Pritha Basu
- Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
| | - Gopinatha Suresh Kumar
- Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India.
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35
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Peng MN, Zhu ZY, Tan LF. Binding Differences of Two Homochiral [Ru(bpy) 2dppz] 2+ Complexes with poly(U)·poly(A)*poly(U) Triplex RNA. Inorg Chem 2017. [PMID: 28636339 DOI: 10.1021/acs.inorgchem.7b00670] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The first investigation of chiral ruthenium(II) complexes Δ- and Λ-[Ru(bpy)2dppz]2+ and triplex RNA poly(U)·poly(A)*poly(U) was carried out, which showed that Δ enantiomer displayed significant ability in stabilizing model triplex RNA.
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Affiliation(s)
- Meng-Na Peng
- Key Laboratory of Environment-friendly Chemistry and Application in Ministry of Education and ‡College of Chemistry, Xiangtan University , Xiangtan 411105, China
| | - Zhi-Yuan Zhu
- Key Laboratory of Environment-friendly Chemistry and Application in Ministry of Education and ‡College of Chemistry, Xiangtan University , Xiangtan 411105, China
| | - Li-Feng Tan
- Key Laboratory of Environment-friendly Chemistry and Application in Ministry of Education and ‡College of Chemistry, Xiangtan University , Xiangtan 411105, China
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36
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Zhu Z, Peng M, Zhang J, Tan L. Interaction of octahedral ruthenium(II) polypyridyl complex [Ru(bpy) 2(PIP)] 2+ with poly(U)·poly(A)*poly(U) triplex: Increasing third-strand stabilization of the triplex without affecting the stability of the duplex. J Inorg Biochem 2017; 169:44-49. [PMID: 28104569 DOI: 10.1016/j.jinorgbio.2017.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 01/10/2023]
Abstract
Triple-helical RNA are of interest because of possible biological roles as well as the potential therapeutic uses of these structures, while the stability of triplexes is usually weaker than that of the Watson-Crick base pairing duplex strand due to the electrostatic repulsion between three polyanionic strands. Therefore, how to increase the stability of the specific sequences of triplexes are of importance. In this paper the binding of a Ru(II) complex, [Ru(bpy)2(PIP)]2+ (bpy=2.2'-bipyridine, PIP=2-phenyl-1H-imidazo[4,5-f]- [1,10]-phenanthroline), with poly(U)·poly(A)*poly(U) triplex has been investigated by spectrophotometry, spectrofluorometry, viscosimetry and circular dichroism. The results suggest that [Ru(bpy)2(PIP)]2+ as a metallointercalator can stabilize poly(U)·poly(A)*poly(U) triplex (where · denotes the Watson-Crick base pairing and * denotes the Hoogsteen base pairing),while it stabilizes third-strand with no obvious effect on the duplex of poly(U)·poly(A), reflecting the binding of this complex with the triplex is favored by the Hoogsteen paired poly(U) third strand to a great extent.
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Affiliation(s)
- Zhiyuan Zhu
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Mengna Peng
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Jingwen Zhang
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, PR China.
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37
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Gomes A, Fernandes I, Teixeira C, Mateus N, Sottomayor MJ, Gomes P. A Quinacrine Analogue Selective Against Gastric Cancer Cells: Insight from Biochemical and Biophysical Studies. ChemMedChem 2016; 11:2703-2712. [PMID: 27863116 DOI: 10.1002/cmdc.201600477] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/11/2016] [Indexed: 12/29/2022]
Abstract
One of the earliest synthetic antimalarial drugs, quinacrine, was recently reported as interesting for the treatment of acute myeloid leukemia. Inspired by this and similar findings, we evaluated a set of quinacrine analogues against gastric (MKN-28), colon (Caco-2), and breast (MFC-7) cancer cell lines and one normal human fibroblast cell line (HFF-1). All the compounds, previously developed by us as dual-stage antimalarial leads, displayed antiproliferative activity, and one of the set stood out as selective toward the gastric cancer cell line, MKN-28. Interestingly, this compound was transported across an in vitro MKN-28 model cell line in low amounts, and approximately 80 % was trapped inside those cells. Nuclear targeting of the same compound and its interactions with calf thymus DNA were assessed through combined fluorescence microscopy, spectroscopy, and calorimetry studies, which provided evidence for the compound's ability to reach the nucleus and to interact with DNA.
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Affiliation(s)
- Ana Gomes
- UCIBIO-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
| | - Iva Fernandes
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
| | - Cátia Teixeira
- UCIBIO-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
| | - Nuno Mateus
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
| | - M J Sottomayor
- CIQ-UP, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
| | - Paula Gomes
- UCIBIO-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal
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38
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An overview on the interaction of phenazinium dye phenosafranine to RNA triple and double helices. Int J Biol Macromol 2016; 86:345-51. [DOI: 10.1016/j.ijbiomac.2016.01.078] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 01/15/2016] [Accepted: 01/21/2016] [Indexed: 12/22/2022]
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39
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Li J, Sun Y, Zhu Z, Zhao H, Tan L. Binding properties of ruthenium(II) complexes [Ru(bpy)2(ppn)](2+) and [Ru(phen)2(ppn)](2+) with triplex RNA: As molecular "light switches" and stabilizers for poly(U)·poly(A)*poly(U) triplex. J Inorg Biochem 2016; 161:128-33. [PMID: 27287059 DOI: 10.1016/j.jinorgbio.2016.04.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/12/2016] [Accepted: 04/18/2016] [Indexed: 01/03/2023]
Abstract
Stable RNA triplexes play key roles in many biological processes, while triplexes are thermodynamically less stable than the corresponding duplexes due to the Hoogsteen base pairing. To understand the factors affecting the stabilization of RNA triplexes by octahedral ruthenium(II) complexes, the binding of [Ru(bpy)2(ppn)](2+) (1, bpy=2,2'-bipyridine, ppn=2,4-diaminopyrimido[5,6-b]dipyrido[2,3-f:2',3'-h]quinoxaline) and [Ru(phen)2(ppn)](2+) (2, phen=1,10-phenanthroline) to poly(U)·poly(A)*poly(U) (· denotes the Watson-Crick base pairing and * denotes the Hoogsteen base pairing) has been investigated. The main results obtained here suggest that complexes 1 and 2 can serve as molecular "light switches" and stabilizers for poly(U)·poly(A)*poly(U), while the effectiveness of complex 2 are more marked, suggesting that the hydrophobicity of ancillary ligands has a significant effect on the two Ru(II) complexes binding to poly(U)·poly(A)*poly(U). This study further advances our knowledge on the binding of RNA triplexes with metal complexes, particularly with octahedral ruthenium polypyridyl complexes.
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Affiliation(s)
- Jia Li
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Yanmei Sun
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Zhiyuan Zhu
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Hong Zhao
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China
| | - Lifeng Tan
- College of Chemistry, Xiangtan University, Xiangtan 411105, PR China; Key Lab of Environmentally Friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan 411105, PR China.
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40
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Haque L, Pradhan AB, Bhuiya S, Das S. Exploring the comparative binding aspects of benzophenanthridine plant alkaloid chelerythrine with RNA triple and double helices: a spectroscopic and calorimetric approach. Phys Chem Chem Phys 2016; 17:17202-13. [PMID: 26073991 DOI: 10.1039/c5cp01737h] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A comparative study on the interaction of a benzophenanthridine alkaloid chelerythrine (CHL) with RNA triplex poly(U).poly(A)*poly(U) (hereafter U.A*U, .(dot) and *(asterisk) represent Watson-Crick and Hoogsteen base pairing respectively) and its parent duplex poly(A).poly(U) (A.U) was carried out by using a combination of various spectroscopic, viscometric and calorimetric techniques. The interaction was characterized by hypochromic and bathochromic effects in the absorption spectrum, the increase of thermal melting temperature, enhancement in solution viscosity, and perturbation in the circular dichroic spectrum. The binding constant calculated by using spectrophotometric data was in the order of 10(5) for both forms of RNA, but it was greater for triplex RNA (30.2 × 10(5) M(-1)) than duplex RNA (3.6 × 10(5) M(-1)). Isothermal titration calorimetric data are in good agreement with the spectrophotometric data. The data indicated stronger binding of CHL to the triplex structure of RNA compared to the native duplex structure. Thermal melting studies indicated greater stabilization of the Hoogsteen base paired third strand of the RNA triplex compared to its Watson-Crick strands. The mode of binding of CHL to both U.A*U and A.U was intercalation as revealed from fluorescence quenching, viscosity measurements and sensitization of the fluorescence experiment. Thermodynamic data obtained from isothermal calorimetric measurements revealed that association was favoured by both a negative enthalpy change and a positive entropy change. Taken together, our results suggest that chelerythrine binds and stabilizes the RNA triplex more strongly than its respective parent duplex. The results presented here may be useful for formulating effective antigene strategies involving benzophenanthridine alkaloids and the RNA triplex.
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Affiliation(s)
- Lucy Haque
- Department of Chemistry, Jadavpur University, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
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41
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Xu L, Hong S, Sun N, Wang K, Zhou L, Ji L, Pei R. Berberine as a novel light-up i-motif fluorescence ligand and its application in designing molecular logic systems. Chem Commun (Camb) 2016; 52:179-82. [DOI: 10.1039/c5cc08242k] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Berberine is reported as a light-up fluorescence ligand for i-motif structures, which enables the development of label-free DNA-based logic gates.
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Affiliation(s)
- Lijun Xu
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
| | - Shanni Hong
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
| | - Na Sun
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
| | - Kewei Wang
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
| | - Lu Zhou
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
| | - Liya Ji
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
| | - Renjun Pei
- Key Laboratory of Nano-Bio Interface
- Division of Nanobiomedicine
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou, 215123
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42
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Rubio AR, Busto N, Leal JM, García B. Doxorubicin binds to duplex RNA with higher affinity than ctDNA and favours the isothermal denaturation of triplex RNA. RSC Adv 2016. [DOI: 10.1039/c6ra21387a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The higher affinity of DOX with AU to give the intercalated complex AU/DOX is responsible for the disproportionation of the groove binding complex, UAU/DOX, to give rise to the AU/DOX and the U/DOX complexes at 25 °C
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Affiliation(s)
- Ana R. Rubio
- Chemistry Department
- University of Burgos
- 09001 Burgos
- Spain
| | - Natalia Busto
- Chemistry Department
- University of Burgos
- 09001 Burgos
- Spain
| | - José M. Leal
- Chemistry Department
- University of Burgos
- 09001 Burgos
- Spain
| | - Begoña García
- Chemistry Department
- University of Burgos
- 09001 Burgos
- Spain
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43
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Kumar GS, Basu A. The use of calorimetry in the biophysical characterization of small molecule alkaloids binding to RNA structures. Biochim Biophys Acta Gen Subj 2015; 1860:930-944. [PMID: 26522497 DOI: 10.1016/j.bbagen.2015.10.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/06/2015] [Accepted: 10/27/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND RNA has now emerged as a potential target for therapeutic intervention. RNA targeted drug design requires detailed thermodynamic characterization that provides new insights into the interactions and this together with structural data, may be used in rational drug design. The use of calorimetry to characterize small molecule-RNA interactions has emerged as a reliable and sensitive tool after the recent advancements in biocalorimetry. SCOPE OF THE REVIEW This review summarizes the recent advancements in thermodynamic characterization of small molecules, particularly some natural alkaloids binding to various RNA structures. Thermodynamic characterization provides information that can supplement structural data leading to more effective drug development protocols. MAJOR CONCLUSIONS This review provides a concise report on the use of isothermal titration calorimetry (ITC) and differential scanning calorimetry (DSC) techniques in characterizing small molecules, mostly alkaloids-RNA interactions with particular reference to binding of tRNA, single stranded RNA, double stranded RNA, poly(A), triplex RNA. GENERAL SIGNIFICANCE It is now apparent that a combination of structural and thermodynamic data is essential for rational design of specific RNA targeted drugs. Recent advancements in biocalorimetry instrumentation have led to detailed understanding of the thermodynamics of small molecules binding to various RNA structures paving the path for the development of many new natural and synthetic molecules as specific binders to various RNA structures. RNA targeted drug design, that remained unexplored, will immensely benefit from the calorimetric studies leading to the development of effective drugs for many diseases.
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Affiliation(s)
- Gopinatha Suresh Kumar
- Biophysical Chemistry Laboratory, Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India.
| | - Anirban Basu
- Biophysical Chemistry Laboratory, Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
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44
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Zhang H, Liu X, He X, Liu Y, Tan L. Experimental and density functional theory (DFT) studies on the interactions of Ru(II) polypyridyl complexes with the RAN triplex poly(U)˙poly(A)*poly(U). Metallomics 2015; 6:2148-56. [PMID: 25313017 DOI: 10.1039/c4mt00175c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
There is renewed interest in investigating triple helices because these novel structures have been implicated as a possible means of controlling cellular processes by endogenous or exogenous mechanisms. Due to the Hoogsteen base pairing, triple helices are, however, thermodynamically less stable than the corresponding duplexes. The poor stability of triple helices limits their practical applications under physiological conditions. In contrast to DNA triple helices, small molecules stabilizing RNA triple helices at present are less well established. Furthermore, most of these studies are limited to organic compounds and, to a far lesser extent, to metal complexes. In this work, two Ru(II) complexes, [Ru(bpy)2(btip)](2+) (Ru1) and [Ru(phen)2(btip)](2+) (Ru2), have been synthesized and characterized. The binding properties of the two metal complexes with the triple RNA poly(U)˙poly(A)*poly(U) were studied by various biophysical and density functional theory methods. The main results obtained here suggest that the slight binding difference in Ru1 and Ru2 may be attributed to the planarity of the intercalative ligand and the LUMO level of Ru(II) complexes. This study further advances our knowledge on the triplex RNA-binding by metal complexes, particularly Ru(II) complexes.
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Affiliation(s)
- Hong Zhang
- College of Chemistry, Xiangtan University, Xiangtan 411105, China
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45
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He X, Li J, Zhang H, Tan L. Effect of a Ru(II) polypyridyl complex [Ru(bpy)2(mdpz)]2+ on the stabilization of the RNA triplex poly(U)·poly(A)*poly(U). MOLECULAR BIOSYSTEMS 2015; 10:2552-7. [PMID: 25010433 DOI: 10.1039/c4mb00304g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
There is renewed interest in investigating triplex nucleic acids because triplexes may be implicated in a range of cellular functions. However, the stabilization of triplex nucleic acids is essential to achieve their biological functions. In contrast to triplex DNA, little has been reported concerning the recognition of triplex RNA by transition-metal complexes at present. We report here a ruthenium(ii) polypyridyl complex, [Ru(bpy)2(mdpz)](2+) (bpy = 2,2'-bipyridine; mdpz = 7,7'-methylenedioxyphenyl-dipyrido-[3,2-a:2',3'-c]phenazine), as a sensitive luminescent probe for poly(U)·poly(A)*poly(U), which can strongly stabilize the triplex RNA from 37.5 to 53.1 °C in solution. The main results further advance our knowledge on the triplex RNA-binding by metal complexes, particularly ruthenium(ii) complexes.
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Affiliation(s)
- Xiaojun He
- College of Chemistry, Xiangtan University, Xiangtan 411105, China
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46
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Basu P, Kumar GS. Structural and thermodynamic basis of interaction of the putative anticancer agent chelerythrine with single, double and triple-stranded RNAs. RSC Adv 2015. [DOI: 10.1039/c5ra00660k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Interaction of chl with poly(uau), poly(au) and poly(u).
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Affiliation(s)
- Pritha Basu
- Biophysical Chemistry Laboratory
- Chemistry Division
- CSIR-Indian Institute of Chemical Biology
- Kolkata 700 032
- India
| | - Gopinatha Suresh Kumar
- Biophysical Chemistry Laboratory
- Chemistry Division
- CSIR-Indian Institute of Chemical Biology
- Kolkata 700 032
- India
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47
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Li J, Sun Y, Xie L, He X, Tan L. Effect of ancillary ligands on the interaction of ruthenium(II) complexes with the triplex RNA poly(U)·poly(A)*poly(U). J Inorg Biochem 2014; 143:56-63. [PMID: 25528478 DOI: 10.1016/j.jinorgbio.2014.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 12/03/2014] [Accepted: 12/03/2014] [Indexed: 01/01/2023]
Abstract
Two new Ru(II) complexes with 1,8-naphthalimide group, [Ru(phen)2(pnip)](2+) (Ru1; phen=1,10-phenanthroline, pnip=2-[N-(p-phenyl)-1,8-napthalimide]imidazo[4',5'-f][1,10]phenanthroline) and [Ru(bpy)2(pnip)](2+) (Ru2; bpy=2,2'-bipyridine), have been synthesized and characterized. The interactions of Ru1 and Ru2 with the triplex RNA poly(U)•poly(A)*poly(U) (where • denotes the Watson-Crick base pairing and * denotes the Hoogsteen base pairing) were studied by various biophysical. Electronic spectra established that the binding affinity for Ru1 was greater than that for Ru2. Fluorescence and viscosity studies gave convincing evidence for a true intercalative binding of both complexes with the RNA triplex. UV melting studies confirmed that the two complexes could stabilize the triplex, whereas the effects of the two complexes on the stability of the Hoogsteen base-paired strand ploy(U) and the Watson-Crick base-paired duplex poly(U)•poly(A) of the triplex were different. In the case of Ru1, the increase of the thermal stability of the Hoogsteen base-paired strand was stronger than that of the Watson-Crick base-paired duplex. However, an opposite effect was observed in the case of Ru2. Circular dichroic studies suggested that the RNA triplex undergoes a conformational transition in the presence of Ru1, whereas the helicity of the RNA triplex still remains A-type in the presence of Ru2. The main results obtained here further advance our knowledge on the interaction of RNA triple-stranded structures with metal complexes, particularly ruthenium(II) complexes.
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Affiliation(s)
- Jia Li
- College of Chemistry, Xiangtan University, Xiangtan, PR China
| | - Yanmei Sun
- College of Chemistry, Xiangtan University, Xiangtan, PR China
| | - Lingjun Xie
- College of Chemistry, Xiangtan University, Xiangtan, PR China
| | - Xiaojun He
- College of Chemistry, Xiangtan University, Xiangtan, PR China
| | - Lifeng Tan
- Key Lab of Environment-friendly Chemistry and Application in Ministry of Education, Xiangtan University, Xiangtan, PR China.
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He XJ, Tan LF. Interactions of octahedral ruthenium(II) polypyridyl complexes with the RNA triplex poly(U)•poly(A)*poly(U) effect on the third-strand stabilization. Inorg Chem 2014; 53:11152-9. [PMID: 25272364 DOI: 10.1021/ic5017565] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Stable triplexes play key roles in many biological processes. Due to the Hoogsteen base pairing, triplexes are, however, thermodynamically less stable than the corresponding duplexes. The poor stabilization of these structures limits their practical applications under physiological conditions. To understand the factors effect on the stabilization of RNA triplexes by octahedral ruthenium(II) complexes, the interactions of [RuL2(uip)](2+) {where L = 2,2'-bipyridine (bpy) or 1,10-phenanthroline phen, uip = 2-(5-uracil)-1H-imidazo[4,5-f][1,10]phenanthroline} with the RNA triplex poly(U)•poly(A)*poly(U) are examined by spectrophotometry, spectrofluorometry, circular dichroism, and viscosimetry in this work. The main results obtained here suggest that the third-strand stabilization depends on the hydrophobicity effects of ancillary ligands bpy and phen.
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Affiliation(s)
- Xiao-Jun He
- Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education, Xiangtan University , Xiangtan 411105, PR China
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Multiple effects of berberine derivatives on colon cancer cells. BIOMED RESEARCH INTERNATIONAL 2014; 2014:924585. [PMID: 25045712 PMCID: PMC4086420 DOI: 10.1155/2014/924585] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/24/2014] [Accepted: 04/24/2014] [Indexed: 01/21/2023]
Abstract
The pharmacological use of the plant alkaloid berberine is based on its antibacterial and anti-inflammatory properties; recently, anticancer activity has been attributed to this compound. To exploit this interesting feature, we synthesized three berberine derivatives, namely, NAX012, NAX014, and NAX018, and we tested their effects on two human colon carcinoma cell lines, that is, HCT116 and SW613-B3, which are characterized by wt and mutated p53, respectively. We observed that cell proliferation is more affected by cell treatment with the derivatives than with the lead compound; moreover, the derivatives proved to induce cell cycle arrest and cell death through apoptosis, thus suggesting that they could be promising anticancer drugs. Finally, we detected typical signs of autophagy in cells treated with berberine derivatives.
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Basu A, Jaisankar P, Kumar GS. Binding of novel 9-O-N-aryl/arylalkyl amino carbonyl methyl berberine analogs to poly(U)-poly(A)·poly(U) triplex and comparison to the duplex poly(A)-poly(U). Mol Biol Rep 2014; 41:5473-83. [PMID: 24874303 DOI: 10.1007/s11033-014-3421-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Accepted: 05/17/2014] [Indexed: 12/14/2022]
Abstract
Interaction of the 9-O-N-aryl/arylalkyl amino carbonyl methyl substituted analogs of the anticancer isoquinoline alkaloid berberine with RNA triplex, poly(U)-poly(A) · poly(U) has been studied in comparison to the duplex poly(A)-poly(U), using multiple biophysical techniques. Spectrophotometric and spectrofluorimetric studies established the non-cooperative binding mode of all the analogs with both the duplex and the triplex. However, berberine exhibited cooperative binding with poly(A)-poly(U) and non-cooperative binding with poly(U)-poly(A) · poly(U). Analog BER1 showed the highest affinity to both the duplex and the triplex followed by BER2 and BER3. The overall binding affinity varied as BER1 > BER2 > BER3 > BER. The magnitude of the quantum efficiency values (Q > 1) revealed that energy was transferred from the bases of the triplex and the duplex to the analogs. Comparative ferrocyanide quenching and viscosity studies unambiguously established a stronger intercalative geometry of the analogs to both the triplex and the duplex in comparison to berberine. Circular dichroism studies revealed that the alkaloids perturbed the conformation of both RNA helices. The binding of all the alkaloids was found to be exothermic from isothermal titration studies. Binding of the analogs was highly entropy driven while that of berberine was enthalpy dominated. The results presented here reveal strong and specific binding of these new berberine analogs to the RNA triplex and duplex and highlight the remarkable influence of the 9-substitution on the interaction profile.
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Affiliation(s)
- Anirban Basu
- Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata, 700 032, India
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