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Ding Z, Cheng W, Liu L, Xu G, Lu Q, Kaplan DL. Nanosized Silk-Magnesium Complexes for Tissue Regeneration. Adv Healthc Mater 2023; 12:e2300887. [PMID: 37317936 DOI: 10.1002/adhm.202300887] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 06/12/2023] [Indexed: 06/16/2023]
Abstract
Metal ions provide multifunctional signals for cell and tissue functions, including regeneration. Inspired by metal-organic frameworks (MOFs), nanosized silk protein aggregates with a high negative charge density are used to form stable silk-magnesium ion complexes. Magnesium ions (Mg ions) are added directly to silk nanoparticle solutions, inducing gelation through the formation of silk-Mg coordination complexes. The Mg ions are released slowly from the nanoparticles through diffusion, with sustained release via tuning the degradation or dissolution of the nanosized silk aggregates. Studies in vitro reveal a dose-dependent influence of Mg ions on angiogenic and anti-inflammatory functions. Silk-Mg ion complexes in the form of hydrogels also stimulate tissue regeneration with a reduced formation of scar tissue in vivo, suggesting potential utility in tissue regeneration.
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Affiliation(s)
- Zhaozhao Ding
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou, 215123, P. R. China
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Weinan Cheng
- Department of Orthopaedics, Shanghai Jiao Tong University Affiliated Shanghai Sixth People's Hospital, Shanghai, 200233, P. R. China
- Department of Orthopedics, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361000, P. R. China
| | - Lutong Liu
- National Engineering Laboratory for Modern Silk & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China
| | - Gang Xu
- Department of Orthopedics, The Affiliated Hospital of Xuzhou Medical University, Lianyungang, 222061, P. R. China
| | - Qiang Lu
- State Key Laboratory of Radiation Medicine and Radiation Protection, Institutes for Translational Medicine, Soochow University, Suzhou, 215123, P. R. China
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
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Liao Z, Fu L, Li P, Wu J, Yuan X, Ning C, Ding Z, Sui X, Liu S, Guo Q. Incorporation of Magnesium Ions into an Aptamer-Functionalized ECM Bioactive Scaffold for Articular Cartilage Regeneration. ACS Appl Mater Interfaces 2023; 15:22944-22958. [PMID: 37134259 DOI: 10.1021/acsami.3c02317] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The regeneration and reconstruction of articular cartilage (AC) after a defect are often difficult. The key to the treatment of AC defects lies in regeneration of the defect site and regulation of the inflammatory response. In this investigation, a bioactive multifunctional scaffold was formulated using the aptamer Apt19S as a mediator for mesenchymal stem cell (MSC)-specific recruitment and the enhancement of cellular chondrogenic and inflammatory regulation through the incorporation of Mg2+. Apt19S, which can recruit MSCs in vitro and in vivo, was chemically conjugated to a decellularized cartilage extracellular matrix (ECM)-lysed scaffold. The results from in vitro experiments using the resulting scaffold demonstrated that the inclusion of Mg2+ could stimulate not only the chondrogenic differentiation of synovial MSCs but also the increased polarization of macrophages toward the M2 phenotype. Additionally, Mg2+ inhibited NLRP3 inflammasome activation, thereby decreasing chondrocyte pyroptosis. Subsequently, Mg2+ was incorporated into the bioactive multifunctional scaffold, and the resulting scaffold promoted cartilage regeneration in vivo. In conclusion, this study confirms that the combination of Mg2+ and aptamer-functionalized ECM scaffolds is a promising strategy for AC regeneration based on in situ tissue engineering and early inflammatory regulation.
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Affiliation(s)
- Zhiyao Liao
- School of Medicine, Nankai University, Tianjin 300071, People's Republic of China
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Liwei Fu
- School of Medicine, Nankai University, Tianjin 300071, People's Republic of China
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Pinxue Li
- School of Medicine, Nankai University, Tianjin 300071, People's Republic of China
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Jiang Wu
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Xun Yuan
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Chao Ning
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Zhengang Ding
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Xiang Sui
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Shuyun Liu
- School of Medicine, Nankai University, Tianjin 300071, People's Republic of China
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
| | - Quanyi Guo
- School of Medicine, Nankai University, Tianjin 300071, People's Republic of China
- Beijing Key Laboratory of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Institute of Orthopedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, People's Republic of China
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Kozin S, Kravtsov A, Ivashchenko L, Dotsenko V, Vasilyeva L, Vasilyev A, Tekutskaya E, Aksenov N, Baryshev M, Dorohova A, Fedulova L, Dzhimak S. Study of the Magnesium Comenate Structure, Its Neuroprotective and Stress-Protective Activity. Int J Mol Sci 2023; 24:ijms24098046. [PMID: 37175753 PMCID: PMC10178379 DOI: 10.3390/ijms24098046] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/24/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
The crystal structure and the biological activity of a new coordination compound of magnesium ions with comenic acid, magnesium comenate, was characterized and studied. Quantitative and qualitative analysis of the compound was investigated in detail using elemental X-ray fluorescent analysis, thermal analysis, IR-Fourier spectrometry, UV spectroscopy, NMR spectroscopy, and X-ray diffraction analysis. Based on experimental analytical data, the empirical formula of magnesium comenate [Mg(HCom)2(H2O)6]·2H2O was established. This complex compound crystallizes with eight water molecules, six of which are the hydration shell of the Mg2+ cation, and two more molecules bind the [Mg(H2O)6]2+ aquacation with ionized ligand molecules by intermolecular hydrogen bonds. The packing of molecules in the crystal lattice is stabilized by a branched system of hydrogen bonds with the participation of solvate water molecules and oxygen atoms of various functional groups of ionized ligand molecules. With regard to the biological activity of magnesium comenate, a neuroprotective, stress-protective, and antioxidant effect was established in in vitro and in vivo models. In in vitro experiments, magnesium comenate protected cerebellar neurons from the toxic effects of glutamate and contributed to the preservation of neurite growth parameters under oxidative stress caused by hydrogen peroxide. In animal studies, magnesium comenate had a stress-protective and antioxidant effect in models of immobilization-cold stress. Oral administration of magnesium comenate at a dose of 2 mg/kg of animal body weight for 3 days before stress exposure and for 3 days during the stress period led to a decrease in oxidative damage and normalization of the antioxidant system of brain tissues against the background of induced stress. The obtained results indicate the advisability of further studies of magnesium comenate as a compound potentially applicable in medicine for the pharmacological correction of conditions associated with oxidative and excitotoxic damage to nerve cells.
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Affiliation(s)
- Stanislav Kozin
- Physics and Technology Faculty, Kuban State University, 350040 Krasnodar, Russia
- Laboratory of Problems of Stable Isotope Spreading in Living Systems, Federal Research Center the Southern Scientific Center, Russian Academy of Sciences, 344006 Rostov-on-Don, Russia
- Laboratory of Technologies for the Production of Physiologically Active Substances, Kuban State Technological University, 350072 Krasnodar, Russia
| | - Alexandr Kravtsov
- Physics and Technology Faculty, Kuban State University, 350040 Krasnodar, Russia
- Laboratory of Problems of Stable Isotope Spreading in Living Systems, Federal Research Center the Southern Scientific Center, Russian Academy of Sciences, 344006 Rostov-on-Don, Russia
- Laboratory of Technologies for the Production of Physiologically Active Substances, Kuban State Technological University, 350072 Krasnodar, Russia
| | - Lev Ivashchenko
- Laboratory of Technologies for the Production of Physiologically Active Substances, Kuban State Technological University, 350072 Krasnodar, Russia
- Faculty of Chemistry and High Technologies, Kuban State University, 350040 Krasnodar, Russia
| | - Victor Dotsenko
- Faculty of Chemistry and High Technologies, Kuban State University, 350040 Krasnodar, Russia
| | - Lada Vasilyeva
- Faculty of Chemistry and High Technologies, Kuban State University, 350040 Krasnodar, Russia
| | - Alexander Vasilyev
- Faculty of Chemistry and High Technologies, Kuban State University, 350040 Krasnodar, Russia
| | - Elena Tekutskaya
- Physics and Technology Faculty, Kuban State University, 350040 Krasnodar, Russia
| | - Nicolai Aksenov
- Faculty of Chemistry and Pharmacy, North Caucasus Federal University, 355017 Stavropol, Russia
| | - Mikhail Baryshev
- Physics and Technology Faculty, Kuban State University, 350040 Krasnodar, Russia
- Laboratory of Problems of Stable Isotope Spreading in Living Systems, Federal Research Center the Southern Scientific Center, Russian Academy of Sciences, 344006 Rostov-on-Don, Russia
| | - Anna Dorohova
- Physics and Technology Faculty, Kuban State University, 350040 Krasnodar, Russia
- Laboratory of Problems of Stable Isotope Spreading in Living Systems, Federal Research Center the Southern Scientific Center, Russian Academy of Sciences, 344006 Rostov-on-Don, Russia
| | - Lilia Fedulova
- Experimental Clinic-Laboratory of Biologically Active Substances of Animal Origin, The V. M. Gorbatov Federal Research Center for Food Systems, Russian Academy of Sciences, 109316 Moscow, Russia
| | - Stepan Dzhimak
- Physics and Technology Faculty, Kuban State University, 350040 Krasnodar, Russia
- Laboratory of Problems of Stable Isotope Spreading in Living Systems, Federal Research Center the Southern Scientific Center, Russian Academy of Sciences, 344006 Rostov-on-Don, Russia
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Abstract
Large-sized bone defects are a great challenge in clinics and considerably impair the quality of patients' daily life. Tissue engineering strategies using cells, scaffolds, and bioactive molecules to regulate the microenvironment in bone regeneration is a promising approach. Zinc, magnesium, and iron ions are natural elements in bone tissue and participate in many physiological processes of bone metabolism and therefore have great potential for bone tissue engineering and regeneration. In this review, we performed a systematic analysis on the effects of zinc, magnesium, and iron ions in bone tissue engineering. We focus on the role of these ions in properties of scaffolds (mechanical strength, degradation, osteogenesis, antibacterial properties, etc.). We hope that our summary of the current research achievements and our notifications of potential strategies to improve the effects of zinc, magnesium, and iron ions in scaffolds for bone repair and regeneration will find new inspiration and breakthroughs to inspire future research.
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Affiliation(s)
- Zhixuan Chen
- School of Medicine, Southeast University, 210009 Nanjing, China.,Center for Stem Cell and Regenerative Medicine, Southeast University, 210009 Nanjing, China
| | - Wei Zhang
- School of Medicine, Southeast University, 210009 Nanjing, China.,Center for Stem Cell and Regenerative Medicine, Southeast University, 210009 Nanjing, China.,Jiangsu Key Laboratory for Biomaterials and Devices, Southeast University, 210096 Nanjing, China.,China Orthopedic Regenerative Medicine Group (CORMed), Hangzhou 310058, China
| | - Mingyue Wang
- School of Medicine, Southeast University, 210009 Nanjing, China.,Center for Stem Cell and Regenerative Medicine, Southeast University, 210009 Nanjing, China
| | - Ludvig J Backman
- Department of Integrative Medical Biology, Anatomy, Umeå University, SE-901 87 Umeå, Sweden.,Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, SE-901 87 Umeå, Sweden
| | - Jialin Chen
- School of Medicine, Southeast University, 210009 Nanjing, China.,Center for Stem Cell and Regenerative Medicine, Southeast University, 210009 Nanjing, China.,Jiangsu Key Laboratory for Biomaterials and Devices, Southeast University, 210096 Nanjing, China.,China Orthopedic Regenerative Medicine Group (CORMed), Hangzhou 310058, China
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Salamanca E, Pan YH, Sun YS, Hsueh HW, Dorj O, Yao WL, Lin JCY, Teng NC, Watanabe I, Abe S, Wu YF, Chang WJ. Magnesium Modified β-Tricalcium Phosphate Induces Cell Osteogenic Differentiation In Vitro and Bone Regeneration In Vivo. Int J Mol Sci 2022; 23:ijms23031717. [PMID: 35163639 PMCID: PMC8836187 DOI: 10.3390/ijms23031717] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 01/27/2023] Open
Abstract
In vitro, in vivo, and clinical studies have shown how the physicochemical and biological properties of β-tricalcium phosphate (β-TCP) work in bone regeneration. This study aimed to improve the properties of β-TCP by achieving optimum surface and bulk β-TCP chemical/physical properties through the hydrothermal addition of magnesium (Mg) and to later establish the biocompatibility of β-TCP/Mg for bone grafting and tissue engineering treatments. Multiple in vitro and in vivo analyses were used to complete β-TCP/Mg physicochemical and biological characterization. The addition of MgO brought about a modest rise in the number of β-TCP surface particles, indicating improvements in alkaline phosphatase (ALP) activity on day 21 (p < 0.05) and in the WST-1assay on all days (p < 0.05), with a corresponding increase in the upregulation of ALP and bone sialoprotein. SEM analyses stated that the surfaces of the β-TCP particles were not altered after the addition of Mg. Micro-CT and histomorphometric analysis from rabbit calvaria critical defects resulted in β-TCP/Mg managing to reform more new bone than the control defects and β-TCP control at 2, 6, and 8 weeks (* p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, and **** p ≤ 0.0001). The hydrothermal addition of MgO to the β-TCP surfaces ameliorated its biocompatibility without altering its surface roughness resulting from the elemental composition while enhancing cell viability and proliferation, inducing more bone regeneration by osteoconduction in vivo and osteoblastic differentiation in vitro.
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Affiliation(s)
- Eisner Salamanca
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
| | - Yu-Hwa Pan
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
- Department of General Dentistry, Chang Gung Memorial Hospital, Taipei 10507, Taiwan
- Graduate Institute of Dental & Craniofacial Science, Chang Gung University, Taoyuan 33305, Taiwan
- School of Dentistry, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Ying-Sui Sun
- School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan;
| | - Hao-Wen Hsueh
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
| | - Odontuya Dorj
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
- Department of Dental Technology and Hygiene, Mongolian National University of Medical Sciences, Ulaanbaatar 14210, Mongolia
| | - Wan-Ling Yao
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
| | - Jerry Chin-Yi Lin
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental, Medicine, Boston, MA 02115, USA
| | - Nai-Chia Teng
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
- Dental Department, Taipei Medical University Hospital, Taipei 11031, Taiwan
| | - Ikki Watanabe
- Department of Gerontology, Tokyo Medical and Dental University, Tokyo 113-8510, Japan;
| | - Shinichi Abe
- Department of Anatomy, Tokyo Dental College, Tokyo 101-0061, Japan;
| | - Yi-Fan Wu
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
- Correspondence: (Y.-F.W.); (W.-J.C.); Tel.: +886-2-2736-1661 (ext. 5148) (Y.-F.W.); +886-2-2736-1661 (ext. 5150) (W.-J.C.)
| | - Wei-Jen Chang
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; (E.S.); (Y.-H.P.); (H.-W.H.); (O.D.); (W.-L.Y.); (J.C.-Y.L.); (N.-C.T.)
- Dental Department, Shuang-ho Hospital, Taipei Medical University, New Taipei City 23561, Taiwan
- Correspondence: (Y.-F.W.); (W.-J.C.); Tel.: +886-2-2736-1661 (ext. 5148) (Y.-F.W.); +886-2-2736-1661 (ext. 5150) (W.-J.C.)
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Hu W, Cheng WC, Wen S, Yuan K. Revealing the Enhancement and Degradation Mechanisms Affecting the Performance of Carbonate Precipitation in EICP Process. Front Bioeng Biotechnol 2021; 9:750258. [PMID: 34888301 PMCID: PMC8650497 DOI: 10.3389/fbioe.2021.750258] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/01/2021] [Indexed: 11/13/2022] Open
Abstract
Given that acid-rich rainfall can cause serious damage to heritage buildings in NW China and subsequently accelerate their aging problem, countermeasures to protect their integrity and also to preserve the continuity of Chinese culture are in pressing need. Enzyme-induced carbonate precipitation (EICP) that modifies the mechanical properties of the soil through enhancing the interparticle bonds by the precipitated crystals and the formation of other carbonate minerals is under a spotlight in recent years. EICP is considered as an alternative to the microbial-induced carbonate precipitation (MICP) because cultivating soil microbes are considered to be challenging in field applications. This study conducts a series of test tube experiments to reproduce the ordinary EICP process, and the produced carbonate precipitation is compared with that of the modified EICP process subjected to the effect of higher MgCl2, NH4Cl, and CaCl2 concentrations, respectively. The modified EICP, subjected to the effect of higher MgCl2 concentrations, performs the best with the highest carbonate precipitation. The enhancement mechanism of carbonate precipitation is well interpreted through elevating the activity of urease enzyme by introducing the magnesium ions. Furthermore, the degradation of carbonate precipitation presents when subjected to the effect of higher NH4Cl concentration. The decreasing activity of urease enzyme and the reverse EICP process play a leading role in degrading the carbonate precipitation. Moreover, when subjected to the effect of higher CaCl2 concentrations, the slower rate of urea hydrolysis and the decreasing activity of urease enzyme are primarily responsible for forming the "hijacking" phenomenon of carbonate precipitation. The findings of this study explore the potential use of the EICP technology for the protection of heritage buildings in NW China.
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Affiliation(s)
- Wenle Hu
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, China
| | - Wen-Chieh Cheng
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, China.,Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, China
| | - Shaojie Wen
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, China
| | - Ke Yuan
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, China
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7
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Zhou H, Yu K, Jiang H, Deng R, Chu L, Cao Y, Zheng Y, Lu W, Deng Z, Liang B. A Three-in-One Strategy: Injectable Biomimetic Porous Hydrogels for Accelerating Bone Regeneration via Shape-Adaptable Scaffolds, Controllable Magnesium Ion Release, and Enhanced Osteogenic Differentiation. Biomacromolecules 2021; 22:4552-4568. [PMID: 34590825 DOI: 10.1021/acs.biomac.1c00842] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The repair of bone defects with irregular shapes, particularly in a minimally invasive manner, remains a major challenge. For synthetic bone grafts, injectable hydrogels are superior to conventional scaffolds because they can adapt satisfactorily to the defect margins and can be injected into deeper areas of injury via a minimally invasive procedure. Based on the poly(lactide-co-glycolide)(PLGA)/1-methyl-2-pyrrolidinone solution reported in our previous study, we successfully synthesized injectable MgO/MgCO3@PLGA (PMM) hydrogels, namely, injectable biomimetic porous hydrogels (IBPHs), to accelerate bone regeneration. In addition to exhibiting excellent injectability, PMM hydrogels could transform into porous scaffolds in situ through a liquid-to-solid phase transition and completely fill irregular bone defects via their superb shape adaptability. Moreover, sustainable and steady release of Mg2+ was achieved by regulating the weight ratio of the incorporated MgO and MgCO3 particles. Via controlled release of Mg2+, PMM hydrogels significantly promoted proliferation, osteogenic differentiation, migration, and biomineral deposition of immortalized mouse embryonic fibroblasts. More importantly, micro-CT imaging and histological analysis indicated that concomitant with their gradual degradation, PMM hydrogels effectively stimulated in situ bone regeneration in rat calvarial defects with an increase in the bone volume fraction of almost 2-fold compared with that in the control group. These findings suggest that injectable PMM hydrogels can satisfactorily match bone defects and form porous scaffolds in situ and can significantly promote bone regeneration via controllable Mg2+ release. The remarkable features of IPBHs may open a new avenue for the exploration of in situ repair systems for irregular bone defects to accelerate bone regeneration and have great potential for clinical translation.
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Affiliation(s)
- Hang Zhou
- Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong Distinct, Chongqing 400010, P. R. China.,Institute of Ultrasound Imaging of Chongqing Medical University; The Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong Distinct, Chongqing 400010, P. R. China
| | - Kexiao Yu
- Department of Orthopedics, Chongqing Traditional Chinese Medicine Hospital, No. 6, Panxi Seventh Branch Road, Jiangbei District, Chongqing 400021, P. R. China
| | - Haitao Jiang
- Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong Distinct, Chongqing 400010, P. R. China
| | - Rui Deng
- Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong Distinct, Chongqing 400010, P. R. China
| | - Lei Chu
- Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong Distinct, Chongqing 400010, P. R. China
| | - Youde Cao
- Department of Pathology, College of Basic Medicine, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong Distinct, Chongqing 400016, P. R. China
| | - Yuanyi Zheng
- Shanghai Institute of Ultrasound in Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Xuhui Distinct, Shanghai 200233, P. R. China
| | - Weizhong Lu
- Department of Orthopedics, Chongqing Traditional Chinese Medicine Hospital, No. 6, Panxi Seventh Branch Road, Jiangbei District, Chongqing 400021, P. R. China
| | - Zhongliang Deng
- Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong Distinct, Chongqing 400010, P. R. China
| | - Bing Liang
- Department of Pathology, College of Basic Medicine, Chongqing Medical University, 1 Yixueyuan Road, Yuzhong Distinct, Chongqing 400016, P. R. China
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8
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Zhao Z, Li G, Ruan H, Chen K, Cai Z, Lu G, Li R, Deng L, Cai M, Cui W. Capturing Magnesium Ions via Microfluidic Hydrogel Microspheres for Promoting Cancellous Bone Regeneration. ACS Nano 2021; 15:13041-13054. [PMID: 34342981 DOI: 10.1021/acsnano.1c02147] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Metal ions are important trace elements in the human body, which directly affect the human metabolism and the regeneration of damaged tissues. For instance, the advanced combination of magnesium ions (Mg2+) and bone repair materials make the composite materials have the function of promoting vascular repair and enhancing the adhesion of osteoblasts. Herein, inspired by magnets to attract metals, we utilized the coordination reaction of metal ion ligand to construct a bisphosphonate-functionalized injectable hydrogel microsphere (GelMA-BP-Mg) which could promote cancellous bone reconstruction of osteoporotic bone defect via capturing Mg2+. By grafting bisphosphonate (BP) on GelMA microspheres, GelMA-BP microspheres could produce powerful Mg2+ capture ability and sustained release performance through coordination reaction, while sustained release BP has bone-targeting properties. In the injectable GelMA-BP-Mg microsphere system, the atomic percentage of captured Mg2+ was 0.6%, and the captured Mg2+ could be effectively released for 18 days. These proved that the composite microspheres could effectively capture Mg2+ and provided the basis for the composite microspheres to activate osteoblasts and endothelial cells and inhibit osteoclasts. Both in vivo and in vitro experimental results revealed that the magnet-inspired Mg2+-capturing composite microspheres are beneficial to osteogenesis and angiogenesis by stimulating osteoblasts and endothelial cells while restraining osteoclasts, and ultimately effectively promote cancellous bone regeneration. This study could provide some meaningful conceptions for the treatment of osteoporotic bone defects on the basis of metal ions.
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Affiliation(s)
- Zhenyu Zhao
- Department of Orthopaedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301 Middle Yanchang Road, Shanghai 200072, People's Republic of China
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Second Road, Shanghai 200025, People's Republic of China
| | - Gen Li
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Second Road, Shanghai 200025, People's Republic of China
| | - Huitong Ruan
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Second Road, Shanghai 200025, People's Republic of China
| | - Keyi Chen
- Department of Orthopaedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301 Middle Yanchang Road, Shanghai 200072, People's Republic of China
| | - Zhengwei Cai
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Second Road, Shanghai 200025, People's Republic of China
| | - Guanghua Lu
- Department of Orthopaedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301 Middle Yanchang Road, Shanghai 200072, People's Republic of China
| | - Runmin Li
- Department of Orthopaedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301 Middle Yanchang Road, Shanghai 200072, People's Republic of China
| | - Lianfu Deng
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Second Road, Shanghai 200025, People's Republic of China
| | - Ming Cai
- Department of Orthopaedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301 Middle Yanchang Road, Shanghai 200072, People's Republic of China
| | - Wenguo Cui
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin Second Road, Shanghai 200025, People's Republic of China
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9
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Szurkowska K, Kazimierczak P, Kolmas J. Mg,Si-Co-Substituted Hydroxyapatite/Alginate Composite Beads Loaded with Raloxifene for Potential Use in Bone Tissue Regeneration. Int J Mol Sci 2021; 22:2933. [PMID: 33805785 DOI: 10.3390/ijms22062933] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/05/2021] [Accepted: 03/11/2021] [Indexed: 01/08/2023] Open
Abstract
Osteoporosis is a worldwide chronic disease characterized by increasing bone fragility and fracture likelihood. In the treatment of bone defects, materials based on calcium phosphates (CaPs) are used due to their high resemblance to bone mineral, their non-toxicity, and their affinity to ionic modifications and increasing osteogenic properties. Moreover, CaPs, especially hydroxyapatite (HA), can be successfully used as a vehicle for local drug delivery. Therefore, the aim of this work was to fabricate hydroxyapatite-based composite beads for potential use as local carriers for raloxifene. HA powder, modified with magnesium and silicon ions (Mg,Si-HA) (both of which play beneficial roles in bone formation), was used to prepare composite beads. As an organic matrix, sodium alginate with chondroitin sulphate and/or keratin was applied. Cross-linking of beads containing raloxifene hydrochloride (RAL) was carried out with Mg ions in order to additionally increase the concentration of this element on the material surface. The morphology and porosity of three different types of beads obtained in this work were characterized by scanning electron microscopy (SEM) and mercury intrusion porosimetry, respectively. The Mg and Si released from the Mg,Si-HA powder and from the beads were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). In vitro RAL release profiles were investigated for 12 weeks and studied using UV/Vis spectroscopy. The beads were also subjected to in vitro biological tests on osteoblast and osteosarcoma cell lines. All the obtained beads revealed a spherical shape with a rough, porous surface. The beads based on chondroitin sulphate and keratin (CS/KER-RAL) with the lowest porosity resulted in the highest resistance to crushing. Results revealed that these beads possessed the most sustained drug release and no burst release effect. Based on the results, it was possible to select the optimal bead composition, consisting of a mixture of chondroitin sulphate and keratin.
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Kognole AA, MacKerell AD. Contributions and competition of Mg 2+ and K + in folding and stabilization of the Twister ribozyme. RNA 2020; 26:1704-1715. [PMID: 32769092 PMCID: PMC7566569 DOI: 10.1261/rna.076851.120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
Native folded and compact intermediate states of RNA typically involve tertiary structures in the presence of divalent ions such as Mg2+ in a background of monovalent ions. In a recent study, we have shown how the presence of Mg2+ impacts the transition from partially unfolded to folded states through a "push-pull" mechanism where the ion both favors and disfavors the sampling of specific phosphate-phosphate interactions. To further understand the ion atmosphere of RNA in folded and partially folded states results from atomistic umbrella sampling and oscillating chemical potential grand canonical Monte Carlo/molecular dynamics (GCMC/MD) simulations are used to obtain atomic-level details of the distributions of Mg2+ and K+ ions around Twister RNA. Results show the presence of 100 mM Mg2+ to lead to increased charge neutralization over that predicted by counterion condensation theory. Upon going from partially unfolded to folded states, overall charge neutralization increases at all studied ion concentrations that, while associated with an increase in the number of direct ion-phosphate interactions, is fully accounted for by the monovalent K+ ions. Furthermore, K+ preferentially interacts with purine N7 atoms of helical regions in partially unfolded states, thereby potentially stabilizing the helical regions. Thus, both secondary helical structures and formation of tertiary structures leads to increased counterion condensation, thereby stabilizing those structural features of Twister. Notably, it is shown that K+ can act as a surrogate for Mg2+ by participating in specific interactions with nonsequential phosphate pairs that occur in the folded state, explaining the ability of Twister to self-cleave at submillimolar Mg2+ concentrations.
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Affiliation(s)
- Abhishek A Kognole
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201, USA
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201, USA
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11
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Qiao X, Yang J, Shang Y, Deng S, Yao S, Wang Z, Guo Y, Peng C. Magnesium-doped Nanostructured Titanium Surface Modulates Macrophage-mediated Inflammatory Response for Ameliorative Osseointegration. Int J Nanomedicine 2020; 15:7185-7198. [PMID: 33061375 PMCID: PMC7532891 DOI: 10.2147/ijn.s239550] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 07/31/2020] [Indexed: 12/29/2022] Open
Abstract
Background Next generation of coating materials on the surface of implants is designed with a paradigm shift from an inert material to an osteoimmunomodulatory material. Regulating immune response to biomedical implants through influencing the polarization of macrophage has been proven to be an effective strategy. Methods Through anodization and hydrothermal treatment, magnesium ion incorporated TiO2 nanotube array (MgN) coating was fabricated on the surface of titanium and it is hypothesized that it has osteoimmunomodulatory properties. To verify this assumption, systematic studies were carried out by in vitro and in vivo experiments. Results Mg ion release behavior results showed that MgN coating was successfully fabricated on the surface of titanium using anodization and hydrothermal technology. Scanning electron microscopy (SEM) images showed the morphology of the MgN coating on the titanium. The expression of inflammation-related genes (IL-6, IL-1β, TNF-α) was downregulated in MgN group compared with TiO2 nanotube (NT) and blank Ti groups, but anti-inflammatory genes (IL-10 and IL-1ra) were remarkably upregulated in the MgN group. The in vitro and in vivo results demonstrated that MgN coating influenced macrophage polarization toward the M2 phenotype compared with NT and blank-Ti groups, which enhanced osteogenic differentiation of rat bone mesenchymal stem cells rBMSCs in conditioned media (CM) generated by macrophages. Conclusion MgN coating on the titanium endowed the surface with immune-regulatory features and exerted an advantageous effect on osteogenesis, thereby providing excellent strategies for the surface modification of biomedical implants.
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Affiliation(s)
- Xinrui Qiao
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Jie Yang
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Yuli Shang
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Shu Deng
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Shiyu Yao
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Zhe Wang
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Yi Guo
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
| | - Cheng Peng
- Department of Stomatology, The Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China
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Yuan Z, Wan Z, Wei P, Lu X, Mao J, Cai Q, Zhang X, Yang X. Dual-Controlled Release of Icariin/Mg 2+ from Biodegradable Microspheres and Their Synergistic Upregulation Effect on Bone Regeneration. Adv Healthc Mater 2020; 9:e2000211. [PMID: 32338458 DOI: 10.1002/adhm.202000211] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/10/2020] [Indexed: 12/15/2022]
Abstract
Current scaffolds applied for bone tissue engineering are still lacking sufficient osteogenic capacity to induce efficient bone regeneration. Biodegradable microsphere-type scaffolds are designed to achieve the dual-controlled release of a Chinese medicine (i.e., icariin, ICA) and a bioactive ion (i.e., Mg2+ ), in order to achieve their synergistic effect on inducing osteogenesis. The hydrophobic icariin is preloaded onto MgO/MgCO3 (1:1 in weight ratio) particles at different amounts and then the particles are encapsulated into biodegradable poly(lactide-co-glycolide) (PLGA) microspheres (PMI) at a fixed fraction (20 wt%). Continuous releases of Mg2+ ion and icariin from the microspheres are detected, showing dependence on icariin amounts. At an optimized moderate loading amount, the resulting PMI-M microspheres display the strongest activation effect on cell biological behaviors among all the designs. By implanting the PMI-M microspheres into rat calvarial defects for 16 weeks, it is found that they can effectively enhance new bone formation, presenting significantly higher capacity in inducing osteogenesis than PMg (containing MgO/MgCO3 but without icariin) and blank PLGA microspheres. Clearly, the released Mg2+ ions are beneficial to osteogenesis, and the coincorporation of icariin exerts supplemental effects in inducing new bone formation, which suggest a promising strategy to regenerate severe bone injuries by designing a dual-release system.
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Affiliation(s)
- Zuoying Yuan
- State Key Laboratory of Organic‐Inorganic CompositesBeijing University of Chemical Technology Beijing 100029 P. R. China
- Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical Technology Beijing 100029 P. R. China
- Department of Mechanics and Engineering ScienceCollege of EngineeringPeking University Beijing 100871 P. R. China
| | - Zhuo Wan
- State Key Laboratory of Organic‐Inorganic CompositesBeijing University of Chemical Technology Beijing 100029 P. R. China
- Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical Technology Beijing 100029 P. R. China
| | - Pengfei Wei
- State Key Laboratory of Organic‐Inorganic CompositesBeijing University of Chemical Technology Beijing 100029 P. R. China
- Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical Technology Beijing 100029 P. R. China
| | - Xin Lu
- Department of EndodonticsSchool and Hospital of StomatologyTianjin Medical University Tianjin 300070 P. R. China
| | - Jianping Mao
- Department of Spine SurgeryBeijing Jishuitan Hospital Beijing 100035 P. R. China
| | - Qing Cai
- State Key Laboratory of Organic‐Inorganic CompositesBeijing University of Chemical Technology Beijing 100029 P. R. China
- Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical Technology Beijing 100029 P. R. China
| | - Xu Zhang
- Department of EndodonticsSchool and Hospital of StomatologyTianjin Medical University Tianjin 300070 P. R. China
| | - Xiaoping Yang
- State Key Laboratory of Organic‐Inorganic CompositesBeijing University of Chemical Technology Beijing 100029 P. R. China
- Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical Technology Beijing 100029 P. R. China
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Demishtein K, Reifen R, Shemesh M. Antimicrobial Properties of Magnesium Open Opportunities to Develop Healthier Food. Nutrients 2019; 11:E2363. [PMID: 31623397 DOI: 10.3390/nu11102363] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/15/2019] [Accepted: 09/21/2019] [Indexed: 02/07/2023] Open
Abstract
Magnesium is a vital mineral that takes part in hundreds of enzymatic reactions in the human body. In the past several years, new information emerged in regard to the antibacterial effect of magnesium. Here we elaborate on the recent knowledge of its antibacterial effect with emphasis on its ability to impair bacterial adherence and formation complex community of bacterial cells called biofilm. We further talk about its ability to impair biofilm formation in milk that provides opportunity for developing safer and qualitative dairy products. Finally, we describe the pronounced advantages of enrichment of food with magnesium ions, which result in healthier and more efficient food products.
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Hu Y, Chen Z, Hou Z, Li M, Ma B, Luo X, Xue X. Influence of Magnesium Ions on the Preparation and Storage of DNA Tetrahedrons in Micromolar Ranges. Molecules 2019; 24:E2091. [PMID: 31159358 DOI: 10.3390/molecules24112091] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/21/2019] [Accepted: 05/29/2019] [Indexed: 12/12/2022] Open
Abstract
The DNA tetrahedron (Td), as one of the novel DNA-based nanoscale biomaterials, has been extensively studied because of its excellent biocompatibility and increased possibilities for decorating precisely. Although the use of Td in laboratories is well established, knowledge surrounding the factors influencing its preparation and storage is lacking. In this research, we investigated the role of the magnesium ions, which greatly affect the structure and stability of DNA. We assembled 1, 2, 5, 10 and 20 μM Td in buffers containing different Mg2+ concentrations, demonstrating that 2 and 5 mM Mg2+ is optimal in these conditions, and that yields decrease dramatically once the DNA concentration reaches 20 μM or the Mg2+ concentration is lower than 0.5 mM. We also verified that the Td structure is retained better through freeze-thawing than lyophilization. Furthermore, a lower initial Mg2+ (≤2 mM) benefited the maintenance of Td structure in the process of lyophilization. Hence, our research sheds light on the influence of Mg2+ in the process of preparing and storing Td, and also provides some enlightenment on improving yields of other DNA nanostructures.
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15
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Nikonov O, Kravchenko O, Nevskaya N, Stolboushkina E, Garber M, Nikonov S. The third structural switch in the archaeal translation initiation factor 2 (aIF2) molecule and its possible role in the initiation of GTP hydrolysis and the removal of aIF2 from the ribosome. Acta Crystallogr D Struct Biol 2019; 75:392-399. [PMID: 30988256 DOI: 10.1107/s2059798319002304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 02/12/2019] [Indexed: 11/10/2022]
Abstract
The structure of the γ subunit of archaeal translation initiation factor 2 (aIF2) from Sulfolobus solfataricus (SsoIF2γ) was determined in complex with GDPCP (a GTP analog). Crystals were obtained in the absence of magnesium ions in the crystallization solution. They belonged to space group P1, with five molecules in the unit cell. Four of these molecules are related in pairs by a common noncrystallographic twofold symmetry axis, while the fifth has no symmetry equivalent. Analysis of the structure and its comparison with other known aIF2 γ-subunit structures in the GTP-bound state show that (i) the magnesium ion is necessary for the formation and the maintenance of the active form of SsoIF2γ and (ii) in addition to the two previously known structural switches 1 and 2, eukaryotic translation initiation factor 2 (eIF2) and aIF2 molecules have another flexible region (switch 3), the function of which may consist of initiation of the hydrolysis of GTP and the removal of e/aIF2 from the ribosome after codon-anticodon recognition.
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Affiliation(s)
- Oleg Nikonov
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russian Federation
| | - Olesya Kravchenko
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russian Federation
| | - Natalia Nevskaya
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russian Federation
| | - Elena Stolboushkina
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russian Federation
| | - Maria Garber
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russian Federation
| | - Stanislav Nikonov
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russian Federation
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16
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Gao T, Zhang W, Wang Y, Yang G. DNA Compaction and Charge Neutralization Regulated by Divalent Ions in very Low pH Solution. Polymers (Basel) 2019; 11:E337. [PMID: 30960321 PMCID: PMC6419228 DOI: 10.3390/polym11020337] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 02/02/2019] [Accepted: 02/06/2019] [Indexed: 12/11/2022] Open
Abstract
DNA conformation is strongly dependent on the valence of counterions in solution, and a valence of at least three is needed for DNA compaction. Recently, we directly demonstrated DNA compaction and its regulation, mediated by divalent cations, by lowering the pH of a solution. In the present study, we found that the critical electrophoretic mobility of DNA is promoted to around -1.0 × 10-4 cm² V-1 s-1 to incur DNA compaction or condensation in a tri- and tetravalent counterions solution, corresponding to an about 89% neutralized charge fraction of DNA. This is also valid for DNA compaction by divalent counterions in a low pH solution. It is notable that the critical charge neutralization of DNA for compaction is only about 1% higher than the saturated charge fraction of DNA in a mild divalent ion solution. We also found that DNA compaction by divalent cations at low pH is weakened and even decondensed with an increasing concentration of counterions.
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Affiliation(s)
- Tianyong Gao
- College of Mathematical, Physics and Electronic Information Engineering, Wenzhou University, Wenzhou 325035, China.
| | - Wei Zhang
- College of Mathematical, Physics and Electronic Information Engineering, Wenzhou University, Wenzhou 325035, China.
| | - Yanwei Wang
- College of Mathematical, Physics and Electronic Information Engineering, Wenzhou University, Wenzhou 325035, China.
| | - Guangcan Yang
- College of Mathematical, Physics and Electronic Information Engineering, Wenzhou University, Wenzhou 325035, China.
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17
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Yu X, Guan PP, Zhu D, Liang YY, Wang T, Wang ZY, Wang P. Magnesium Ions Inhibit the Expression of Tumor Necrosis Factor α and the Activity of γ-Secretase in a β-Amyloid Protein-Dependent Mechanism in APP/PS1 Transgenic Mice. Front Mol Neurosci 2018; 11:172. [PMID: 29899688 PMCID: PMC5988891 DOI: 10.3389/fnmol.2018.00172] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/07/2018] [Indexed: 11/19/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disease characterized by cognitive impairment. The neuropathological features of AD are the aggregation of extracellular amyloid β-protein (Aβ) and tau phosphorylation. Recently, AD was found to be associated with magnesium ion (Mg2+) deficit and tumor necrosis factor-alpha (TNF-α) elevation in the serum or brains of AD patients. To study the relationship between Mg2+ and TNF-α, we used human- or mouse-derived glial and neuronal cell lines or APP/PS1 transgenic (Tg) mice as in vitro and in vivo experimental models, respectively. Our data demonstrates that magnesium-L-threonate (MgT) can decrease the expression of TNF-α by restoring the levels of Mg2+ in glial cells. In addition, PI3-K/AKT and NF-κB signals play critical roles in mediating the effects of Mg2+ on suppressing the expression of TNF-α. In neurons, Mg2+ elevation showed similar suppressive effects on the expression of presenilin enhancer 2 (PEN2) and nicastrin (NCT) through a PI3-K/AKT and NF-κB-dependent mechanism. As the major components of γ-secretase, overexpression of presenilin 1 (PS1), PEN2 and NCT potentially promote the synthesis of Aβ, which in turn activates TNF-α in glial cells. Reciprocally, TNF-α stimulates the expression of PEN2 and NCT in neurons. The crosstalk between TNF-α and Aβ in glial cells and neurons could ultimately aggravate the development and progression of AD.
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Affiliation(s)
- Xin Yu
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Pei-Pei Guan
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Di Zhu
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Yun-Yue Liang
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Tao Wang
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Zhan-You Wang
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Pu Wang
- College of Life and Health Sciences, Northeastern University, Shenyang, China
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Abstract
Interaction with divalent cations is of paramount importance for RNA structural stability and function. We report here a detailed molecular dynamics study of all the possible binding sites for Mg2+ on an RNA duplex, including both direct (inner sphere) and indirect (outer sphere) binding. In order to tackle sampling issues, we develop a modified version of bias-exchange metadynamics, which allows us to simultaneously compute affinities with previously unreported statistical accuracy. Results correctly reproduce trends observed in crystallographic databases. Based on this, we simulate a carefully chosen set of models that allows us to quantify the effects of competition with monovalent cations, RNA flexibility, and RNA hybridization. Our simulations reproduce the decrease and increase of Mg2+ affinity due to ion competition and hybridization, respectively, and predict that RNA flexibility has a site-dependent effect. This suggests a nontrivial interplay between RNA conformational entropy and divalent cation binding.
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Affiliation(s)
- Richard A Cunha
- Scuola Internazionale Superiore di Studi Avanzati-SISSA, 34136, Trieste, Italy
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati-SISSA, 34136, Trieste, Italy
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19
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Rathore SS, Raman T, Ramakrishnan J. Magnesium Ion Acts as a Signal for Capsule Induction in Cryptococcus neoformans. Front Microbiol 2016; 7:325. [PMID: 27014245 PMCID: PMC4791529 DOI: 10.3389/fmicb.2016.00325] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 02/29/2016] [Indexed: 12/24/2022] Open
Abstract
Cryptococcal meningitis caused by Cryptococcus neoformans, is a common opportunistic neural infection in immunocompromised individuals. Cryptococcus meningitis is associated with fungal burden with larger capsule size in cerebrospinal fluid (CSF). To understand the role of CSF constituents in capsule enlargement, we have evaluated the effect of artificial CSF on capsule induction in comparison with various other capsule inducing media. Two different strains of C. neoformans, an environmental and a clinical isolates were used in the present study. While comparing the various capsule inducing media for the two different strains of C. neoformans, it was observed that the capsule growth was significantly increased when grown in artificial CSF at pH 5.5, temperature 34°C for ATCC C. neoformans and 37°C for Clinical C. neoformans and with an incubation period of 72 h. In addition, artificial CSF supports biofilm formation in C. neoformans. While investigating the individual components of artificial CSF, we found that Mg2+ ions influence the capsule growth in both environmental and clinical strains of C. neoformans. To confirm our results we studied the expression of four major CAP genes namely, CAP10, CAP59, CAP60, and CAP64 in various capsule inducing media and in different concentrations of Mg2+ and Ca2+. Our results on gene expression suggest that, Mg2+ does have an effect on CAP gene expression, which are important for capsule biosynthesis and virulence. Our findings on the role of Mg2+ ion as a signal for capsule induction will promote a way to elucidate the control mechanisms for capsule biosynthesis in C. neoformans.
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Affiliation(s)
- Sudarshan S Rathore
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, Shanmugha Arts, Science, Technology & Research Academy University Thanjavur, India
| | - Thiagarajan Raman
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, Shanmugha Arts, Science, Technology & Research Academy University Thanjavur, India
| | - Jayapradha Ramakrishnan
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, Shanmugha Arts, Science, Technology & Research Academy University Thanjavur, India
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Oknin H, Steinberg D, Shemesh M. Magnesium ions mitigate biofilm formation of Bacillus species via downregulation of matrix genes expression. Front Microbiol 2015; 6:907. [PMID: 26441856 PMCID: PMC4561805 DOI: 10.3389/fmicb.2015.00907] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/19/2015] [Indexed: 11/13/2022] Open
Abstract
The objective of this study was to investigate the effect of Mg(2+) ions on biofilm formation by Bacillus species, which are considered as problematic microorganisms in the food industry. We found that magnesium ions are capable to inhibit significantly biofilm formation of Bacillus species at 50 mM concentration and higher. We further report that Mg(2+) ions don't inhibit bacterial growth at elevated concentrations; hence, the mode of action of Mg(2+) ions is apparently specific to inhibition of biofilm formation. Biofilm formation depends on the synthesis of extracellular matrix, whose production in Bacillus subtilis is specified by two major operons: the epsA-O and tapA operons. We analyzed the effect of Mg(2+) ions on matrix gene expression using transcriptional fusions of the promoters for eps and tapA to the gene encoding β galactosidase. The expression of the two matrix operons was reduced drastically in response to Mg(2+) ions suggesting about their inhibitory effect on expression of the matrix genes in B. subtilis. Since the matrix gene expression is tightly controlled by Spo0A dependent pathway, we conclude that Mg(2+) ions could affect the signal transduction for biofilm formation through this pathway.
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Affiliation(s)
- Hilla Oknin
- Department of Food Quality and Safety, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization, The Volcani CenterBet-Dagan, Israel
- Biofilm Research Laboratory, Faculty of Dental Medicine, Institute of Dental Sciences, Hebrew University-HadassahJerusalem, Israel
| | - Doron Steinberg
- Biofilm Research Laboratory, Faculty of Dental Medicine, Institute of Dental Sciences, Hebrew University-HadassahJerusalem, Israel
| | - Moshe Shemesh
- Department of Food Quality and Safety, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization, The Volcani CenterBet-Dagan, Israel
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Bonneau E, Girard N, Lemieux S, Legault P. The NMR structure of the II-III-VI three-way junction from the Neurospora VS ribozyme reveals a critical tertiary interaction and provides new insights into the global ribozyme structure. RNA 2015; 21:1621-32. [PMID: 26124200 PMCID: PMC4536322 DOI: 10.1261/rna.052076.115] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 06/08/2015] [Indexed: 05/04/2023]
Abstract
As part of an effort to structurally characterize the complete Neurospora VS ribozyme, NMR solution structures of several subdomains have been previously determined, including the internal loops of domains I and VI, the I/V kissing-loop interaction and the III-IV-V junction. Here, we expand this work by determining the NMR structure of a 62-nucleotide RNA (J236) that encompasses the VS ribozyme II-III-VI three-way junction and its adjoining stems. In addition, we localize Mg(2+)-binding sites within this structure using Mn(2+)-induced paramagnetic relaxation enhancement. The NMR structure of the J236 RNA displays a family C topology with a compact core stabilized by continuous stacking of stems II and III, a cis WC/WC G•A base pair, two base triples and two Mg(2+) ions. Moreover, it reveals a remote tertiary interaction between the adenine bulges of stems II and VI. Additional NMR studies demonstrate that both this bulge-bulge interaction and Mg(2+) ions are critical for the stable folding of the II-III-VI junction. The NMR structure of the J236 RNA is consistent with biochemical studies on the complete VS ribozyme, but not with biophysical studies performed with a minimal II-III-VI junction that does not contain the II-VI bulge-bulge interaction. Together with previous NMR studies, our findings provide important new insights into the three-dimensional architecture of this unique ribozyme.
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Affiliation(s)
- Eric Bonneau
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Nicolas Girard
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Sébastien Lemieux
- Département d'Informatique et de Recherche Opérationnelle et Institut de Recherche en Immunologie et en Cancérologie, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
| | - Pascale Legault
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
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Lozano G, Fernandez N, Martinez-Salas E. Magnesium-dependent folding of a picornavirus IRES element modulates RNA conformation and eIF4G interaction. FEBS J 2014; 281:3685-700. [PMID: 24961997 PMCID: PMC4163634 DOI: 10.1111/febs.12890] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 06/12/2014] [Accepted: 06/20/2014] [Indexed: 12/24/2022]
Abstract
Internal ribosome entry site (IRES) elements are high-order RNA structures that promote internal initiation of translation to allow protein synthesis under situations that compromise the general cap-dependent translation mechanism. Picornavirus IRES elements are highly efficient elements with a modular RNA structure organization. Here we investigated the effect of Mg(2+) concentration on the local flexibility and solvent accessibility of the foot-and-mouth disease virus (FMDV) IRES element measured on the basis of selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) reactivity and hydroxyl radical cleavage. We have found that Mg(2+) concentration affects the organization of discrete IRES regions, mainly the apical region of domain 3, the 10 nt loop of domain 4, and the pyrimidine tract of domain 5. In support of the effect of RNA structure on IRES activity, substitution or deletion mutants of the 10 nt loop of domain 4 impair internal initiation. In addition, divalent cations affect the binding of eIF4G, a eukaryotic initiation factor that is essential for IRES-dependent translation that interacts with domain 4. Binding of eIF4G is favored by the local RNA flexibility adopted at low Mg(2+) concentration, while eIF4B interacts with the IRES independently of the compactness of the RNA structure. Our study shows that the IRES element adopts a near-native structure in the absence of proteins, shedding light on the influence of Mg(2+) ions on the local flexibility and binding of eIF4G in a model IRES element.
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Affiliation(s)
- Gloria Lozano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Cantoblanco, Spain
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He GJ, Liu WF, Yan YB. Dissimilar roles of the four conserved acidic residues in the thermal stability of poly(A)-specific ribonuclease. Int J Mol Sci 2011; 12:2901-16. [PMID: 21686157 DOI: 10.3390/ijms12052901] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 03/23/2011] [Accepted: 04/18/2011] [Indexed: 11/17/2022] Open
Abstract
Divalent metal ions are essential for the efficient catalysis and structural stability of many nucleotidyl-transfer enzymes. Poly(A)-specific ribonuclease (PARN) belongs to the DEDD superfamily of 3′-exonucleases, and the active site of PARN contains four conserved acidic amino acid residues that coordinate two Mg2+ ions. In this research, we studied the roles of these four acidic residues in PARN thermal stability by mutational analysis. It was found that Mg2+ significantly decreased the rate but increased the aggregate size of the 54 kDa wild-type PARN in a concentration-dependent manner. All of the four mutants decreased PARN thermal aggregation, while the aggregation kinetics of the mutants exhibited dissimilar Mg2+-dependent behavior. A comparison of the kinetic parameters indicated that Asp28 was the most crucial one to the binding of the two Mg2+ ions, while metal B might be more important in PARN structural stability. The spectroscopic and aggregation results also suggested that the alterations in the active site structure by metal binding or mutations might lead to a global conformational change of the PARN molecule.
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Tan ZJ, Chen SJ. Importance of diffuse metal ion binding to RNA. Met Ions Life Sci 2011; 9:101-24. [PMID: 22010269 PMCID: PMC4883094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
RNAs are highly charged polyanionic molecules. RNA structure and function are strongly correlated with the ionic condition of the solution. The primary focus of this article is on the role of diffusive ions in RNA folding. Due to the long-range nature of electrostatic interactions, the diffuse ions can contribute significantly to RNA structural stability and folding kinetics. We present an overview of the experimental findings as well as the theoretical developments on the diffuse ion effects in RNA folding. This review places heavy emphasis on the effect of magnesium ions. Magnesium ions play a highly efficient role in stabilizing RNA tertiary structures and promoting tertiary structural folding. The highly efficient role goes beyond the mean-field effect such as the ionic strength. In addition to the effects of specific ion binding and ion dehydration, ion-ion correlation for the diffuse ions can contribute to the efficient role of the multivalent ions such as the magnesium ions in RNA folding.
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Affiliation(s)
- Zhi-Jie Tan
- Department of Physics and Key Laboratory of Artificial Micro- and Nano-Structures of the Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430 072, China
| | - Shi-Jie Chen
- Department of Physics & Astronomy and Department of Biochemistry, University of Missouri, Columbia MO 65211, USA
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Saksmerprome V, Roychowdhury-Saha M, Jayasena S, Khvorova A, Burke DH. Artificial tertiary motifs stabilize trans-cleaving hammerhead ribozymes under conditions of submillimolar divalent ions and high temperatures. RNA 2004; 10:1916-1924. [PMID: 15547137 PMCID: PMC1370680 DOI: 10.1261/rna.7159504] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Accepted: 09/27/2004] [Indexed: 05/24/2023]
Abstract
Tertiary stabilizing motifs (TSMs) between terminal loops or internal bulges facilitate folding of natural hammerhead ribozymes (hRz) under physiological conditions. However, both substrate and enzyme strands contribute nucleotides to the TSMs of trans-cleaving hRz, complicating the design of hRz that exploit TSMs to target specific mRNA. To overcome this limitation, we used SELEX to identify new, artificial TSMs that are less sensitive to sequence context. Nucleotides in loop II or in a bulge within the ribozyme strand of stem I were randomized, while the interaction partner was held constant. All nucleotides of the substrate pair with the ribozyme, minimizing their possible recruitment into the TSM, as such recruitment could constrain choice of candidate target sequences. Six cycles of selection identified cis-acting ribozymes that were active in 100 microM MgCl2. The selected motifs partially recapitulate TSMs found in natural hRz, suggesting that the natural motifs are close to optimal for their respective contexts. Ribozyme "RzB" showed enhanced thermal stability by retaining trans-cleavage activity at 80 degrees C in 10 mM MgCl2 and at 70 degrees C in 2 mM MgCl2. A variant of ribozyme "RzB" with a continuously paired stem 1 rapidly lost activity as temperature was increased. The selected motifs are modular, in that they permit trans-cleavage of several substrates in submillimolar MgCl2, including two substrates derived from the U5 genomic region of HIV-1. The new, artificial tertiary stabilized hRz are thus nearly independent of sequence context and enable for the first time the use of highly active hRz targeting almost any mRNA at physiologically relevant magnesium concentrations.
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