1
|
Kontoghiorghes GJ. The Importance and Essentiality of Natural and Synthetic Chelators in Medicine: Increased Prospects for the Effective Treatment of Iron Overload and Iron Deficiency. Int J Mol Sci 2024; 25:4654. [PMID: 38731873 PMCID: PMC11083551 DOI: 10.3390/ijms25094654] [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: 04/02/2024] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 05/13/2024] Open
Abstract
The supply and control of iron is essential for all cells and vital for many physiological processes. All functions and activities of iron are expressed in conjunction with iron-binding molecules. For example, natural chelators such as transferrin and chelator-iron complexes such as haem play major roles in iron metabolism and human physiology. Similarly, the mainstay treatments of the most common diseases of iron metabolism, namely iron deficiency anaemia and iron overload, involve many iron-chelator complexes and the iron-chelating drugs deferiprone (L1), deferoxamine (DF) and deferasirox. Endogenous chelators such as citric acid and glutathione and exogenous chelators such as ascorbic acid also play important roles in iron metabolism and iron homeostasis. Recent advances in the treatment of iron deficiency anaemia with effective iron complexes such as the ferric iron tri-maltol complex (feraccru or accrufer) and the effective treatment of transfusional iron overload using L1 and L1/DF combinations have decreased associated mortality and morbidity and also improved the quality of life of millions of patients. Many other chelating drugs such as ciclopirox, dexrazoxane and EDTA are used daily by millions of patients in other diseases. Similarly, many other drugs or their metabolites with iron-chelation capacity such as hydroxyurea, tetracyclines, anthracyclines and aspirin, as well as dietary molecules such as gallic acid, caffeic acid, quercetin, ellagic acid, maltol and many other phytochelators, are known to interact with iron and affect iron metabolism and related diseases. Different interactions are also observed in the presence of essential, xenobiotic, diagnostic and theranostic metal ions competing with iron. Clinical trials using L1 in Parkinson's, Alzheimer's and other neurodegenerative diseases, as well as HIV and other infections, cancer, diabetic nephropathy and anaemia of inflammation, highlight the importance of chelation therapy in many other clinical conditions. The proposed use of iron chelators for modulating ferroptosis signifies a new era in the design of new therapeutic chelation strategies in many other diseases. The introduction of artificial intelligence guidance for optimal chelation therapeutic outcomes in personalised medicine is expected to increase further the impact of chelation in medicine, as well as the survival and quality of life of millions of patients with iron metabolic disorders and also other diseases.
Collapse
Affiliation(s)
- George J Kontoghiorghes
- Postgraduate Research Institute of Science, Technology, Environment and Medicine, Limassol 3021, Cyprus
| |
Collapse
|
2
|
Hu S, Lin S, Xu H, He X, Chen L, Feng Q, Sun N. Molecular Mechanisms of Iron Transport and Homeostasis Regulated by Antarctic Krill-Derived Heptapeptide-Iron Complex. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:7517-7532. [PMID: 38527166 DOI: 10.1021/acs.jafc.3c05812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
In this study, the molecular mechanisms of iron transport and homeostasis regulated by the Antarctic krill-derived heptapeptide-iron (LVDDHFL-iron) complex were explored. LVDDHFL-iron significantly increased the hemoglobin, serum iron, total iron binding capacity levels, and iron contents in the liver and spleen to normal levels, regulated the gene expressions of iron homeostasis, and enhanced in vivo antioxidant capacity in iron-deficiency anemia mice (P < 0.05). The results revealed that iron ions within LVDDHFL-iron can be transported via the heme transporter and divalent metal transporter-1, and the absorption of LVDDHFL-iron involved receptor-mediated endocytosis. We also found that the transport of LVDDHFL-iron across cells via phagocytosis was facilitated by the up-regulation of the high mobility group protein, heat shock protein β, and V-type proton ATPase subunit, accompanied by the regulatory mechanism of autophagy. These findings provided deeper understandings of the mechanism of LVDDHFL-iron facilitating iron absorption.
Collapse
Affiliation(s)
- Shengjie Hu
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, P. R. China
| | - Songyi Lin
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, P. R. China
- Engineering Research Center of Special Dietary Food, Education Department of Liaoning Province, Dalian 116034, P. R. China
| | - Haowei Xu
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
| | - Xueqing He
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
| | - Lei Chen
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
| | - Qi Feng
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
| | - Na Sun
- SKL of Marine Food Processing & Safety Control, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, P. R. China
- National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, P. R. China
- Engineering Research Center of Special Dietary Food, Education Department of Liaoning Province, Dalian 116034, P. R. China
| |
Collapse
|
3
|
Yang T, Zou Y, Ng HL, Kumar A, Newton SM, Klebba PE. Specificity and mechanism of TonB-dependent ferric catecholate uptake by Fiu. Front Microbiol 2024; 15:1355253. [PMID: 38601941 PMCID: PMC11005823 DOI: 10.3389/fmicb.2024.1355253] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 01/23/2024] [Indexed: 04/12/2024] Open
Abstract
We studied the Escherichia coli outer membrane protein Fiu, a presumed transporter of monomeric ferric catecholates, by introducing Cys residues in its surface loops and modifying them with fluorescein maleimide (FM). Fiu-FM bound iron complexes of the tricatecholate siderophore enterobactin (FeEnt) and glucosylated enterobactin (FeGEnt), their dicatecholate degradation product Fe(DHBS)2 (FeEnt*), the monocatecholates dihydroxybenzoic acid (FeDHBA) and dihydroxybenzoyl serine (FeDHBS), and the siderophore antibiotics cefiderocol (FDC) and MB-1. Unlike high-affinity ligand-gated porins (LGPs), Fiu-FM had only micromolar affinity for iron complexes. Its apparent KD values for FeDHBS, FeDHBA, FeEnt*, FeEnt, FeGEnt, FeFDC, and FeMB-1 were 0.1, 0.7, 0.7, 1.0, 0.3, 0.4, and 4 μM, respectively. Despite its broad binding abilities, the transport repertoires of E. coli Fiu, as well as those of Cir and FepA, were less broad. Fiu only transported FeEnt*. Cir transported FeEnt* and FeDHBS (weakly); FepA transported FeEnt, FeEnt*, and FeDHBA. Both Cir and FepA bound FeGEnt, albeit with lower affinity. Related transporters of Acinetobacter baumannii (PiuA, PirA, BauA) had similarly moderate affinity and broad specificity for di- or monomeric ferric catecholates. Both microbiological and radioisotopic experiments showed Fiu's exclusive transport of FeEnt*, rather than ferric monocatecholate compounds. Molecular docking and molecular dynamics simulations predicted three binding sites for FeEnt*in the external vestibule of Fiu, and a fourth site deeper in its interior. Alanine scanning mutagenesis in the outermost sites (1a, 1b, and 2) decreased FeEnt* binding affinity as much as 20-fold and reduced or eliminated FeEnt* uptake. Finally, the molecular dynamics simulations suggested a pathway of FeEnt* movement through Fiu that may generally describe the process of metal transport by TonB-dependent receptors.
Collapse
Affiliation(s)
| | | | | | | | | | - Phillip E. Klebba
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, United States
| |
Collapse
|
4
|
Yan J, Nielsen TB, Lu P, Talyansky Y, Slarve M, Reza H, Novakovic B, Netea MG, Keller AE, Warren T, DiGiandomenico A, Sellman BR, Luna BM, Spellberg B. A protein-free vaccine stimulates innate immunity and protects against nosocomial pathogens. Sci Transl Med 2023; 15:eadf9556. [PMID: 37792959 PMCID: PMC10947341 DOI: 10.1126/scitranslmed.adf9556] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 08/15/2023] [Indexed: 10/06/2023]
Abstract
Traditional vaccines are difficult to deploy against the diverse antimicrobial-resistant, nosocomial pathogens that cause health care-associated infections. We developed a protein-free vaccine composed of aluminum hydroxide, monophosphoryl lipid A, and fungal mannan that improved survival and reduced bacterial burden of mice with invasive blood or lung infections caused by methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, extended-spectrum beta-lactamase-expressing Escherichia coli, and carbapenem-resistant strains of Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The vaccine also conferred protection against the fungi Rhizopus delemar and Candida albicans. Efficacy was apparent by 24 hours and lasted for up to 28 days after a single vaccine dose, with a second dose restoring efficacy. The vaccine acted through stimulation of the innate, rather than the adaptive, immune system, as demonstrated by efficacy in the absence of lymphocytes that were abrogated by macrophage depletion. A role for macrophages was further supported by the finding that vaccination induced macrophage epigenetic alterations that modulated phagocytosis and the inflammatory response to infection. Together, these data show that this protein-free vaccine is a promising strategy to prevent deadly antimicrobial-resistant health care-associated infections.
Collapse
Affiliation(s)
- Jun Yan
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Travis B. Nielsen
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
- UC San Diego School of Medicine, University of California San Diego, San Diego, CA 92093, USA
| | - Peggy Lu
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Yuli Talyansky
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Matt Slarve
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Hernan Reza
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Boris Novakovic
- Murdoch Children’s Research Institute and Department of Paediatrics, University of Melbourne, Royal Children’s Hospital, Parkville, VIC 3052, Australia
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, 6525 GA Nijmegen, Netherlands
- Department of Immunology and Metabolism, Life and Medical Sciences Institute, University of Bonn, 53115 Bonn, Germany
| | - Ashley E. Keller
- AstraZeneca Inc., Early Vaccines and Immune Therapies, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD 20878, USA
| | - Troy Warren
- AstraZeneca Inc., Early Vaccines and Immune Therapies, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD 20878, USA
| | - Antonio DiGiandomenico
- AstraZeneca Inc., Early Vaccines and Immune Therapies, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD 20878, USA
| | - Bret R. Sellman
- AstraZeneca Inc., Early Vaccines and Immune Therapies, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD 20878, USA
| | - Brian M. Luna
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Brad Spellberg
- Los Angeles General Medical Center, Los Angeles, CA 90033, USA
| |
Collapse
|
5
|
Kontoghiorghes GJ. The Vital Role Played by Deferiprone in the Transition of Thalassaemia from a Fatal to a Chronic Disease and Challenges in Its Repurposing for Use in Non-Iron-Loaded Diseases. Pharmaceuticals (Basel) 2023; 16:1016. [PMID: 37513928 PMCID: PMC10384919 DOI: 10.3390/ph16071016] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/13/2023] [Accepted: 07/15/2023] [Indexed: 07/30/2023] Open
Abstract
The iron chelating orphan drug deferiprone (L1), discovered over 40 years ago, has been used daily by patients across the world at high doses (75-100 mg/kg) for more than 30 years with no serious toxicity. The level of safety and the simple, inexpensive synthesis are some of the many unique properties of L1, which played a major role in the contribution of the drug in the transition of thalassaemia from a fatal to a chronic disease. Other unique and valuable clinical properties of L1 in relation to pharmacology and metabolism include: oral effectiveness, which improved compliance compared to the prototype therapy with subcutaneous deferoxamine; highly effective iron removal from all iron-loaded organs, particularly the heart, which is the major target organ of iron toxicity and the cause of mortality in thalassaemic patients; an ability to achieve negative iron balance, completely remove all excess iron, and maintain normal iron stores in thalassaemic patients; rapid absorption from the stomach and rapid clearance from the body, allowing a greater frequency of repeated administration and overall increased efficacy of iron excretion, which is dependent on the dose used and also the concentration achieved at the site of drug action; and its ability to cross the blood-brain barrier and treat malignant, neurological, and microbial diseases affecting the brain. Some differential pharmacological activity by L1 among patients has been generally shown in relation to the absorption, distribution, metabolism, elimination, and toxicity (ADMET) of the drug. Unique properties exhibited by L1 in comparison to other drugs include specific protein interactions and antioxidant effects, such as iron removal from transferrin and lactoferrin; inhibition of iron and copper catalytic production of free radicals, ferroptosis, and cuproptosis; and inhibition of iron-containing proteins associated with different pathological conditions. The unique properties of L1 have attracted the interest of many investigators for drug repurposing and use in many pathological conditions, including cancer, neurodegenerative conditions, microbial conditions, renal conditions, free radical pathology, metal intoxication in relation to Fe, Cu, Al, Zn, Ga, In, U, and Pu, and other diseases. Similarly, the properties of L1 increase the prospects of its wider use in optimizing therapeutic efforts in many other fields of medicine, including synergies with other drugs.
Collapse
Affiliation(s)
- George J Kontoghiorghes
- Postgraduate Research Institute of Science, Technology, Environment and Medicine, Limassol 3021, Cyprus
| |
Collapse
|
6
|
Khan S, Cho WC, Hussain A, Azimi S, Babadaei MMN, Bloukh SH, Edis Z, Saeed M, Ten Hagen TLM, Ahmadi H, Ale-Ebrahim M, Jaragh-Alhadad LA, Khan RH, Falahati M, Zhang X, Bai Q. The interaction mechanism of plasma iron transport protein transferrin with nanoparticles. Int J Biol Macromol 2023; 240:124441. [PMID: 37060978 DOI: 10.1016/j.ijbiomac.2023.124441] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 03/21/2023] [Accepted: 04/10/2023] [Indexed: 04/17/2023]
Abstract
In the biological systems, exposure to nanoparticles (NPs) can cause complicated interactions with proteins, the formation of protein corona and structural changes to proteins. These changes depend not only on NP physicochemical properties, but also on the intrinsic stability of protein molecules. Although, the formation of protein corona on the surface of NPs and the underlying mechanisms have been fully explored in various studies, no comprehensive review has discussed the direct biochemical and biophysical interactions between NPs and blood proteins, particularly transferrin. In this review, we first discussed the interaction of NPs with proteins to comprehend the effects of physicochemical properties of NPs on protein structure. We then overviewed the transferrin structure and its direct interaction with NPs to explore transferrin stability and its iron ion (Fe3+) release behavior. Afterwards, we surveyed the various biological functions of transferrin, such as Fe3+ binding, receptor binding, antibacterial activity, growth, differentiation, and coagulation, followed by the application of transferrin-modified NPs in the development of drug delivery systems for cancer therapy. We believe that this study can provide useful insight into the design and development of bioconjugates containing NP-transferrin for potential biomedical applications.
Collapse
Affiliation(s)
- Suliman Khan
- The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, China; Department of Medical Lab Technology, The University of Haripur, Pakistan
| | - William C Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong
| | - Arif Hussain
- School of Life Sciences, Manipal Academy of Higher Education, Dubai, United Arab Emirates
| | - Sadaf Azimi
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Mohammad Mahdi Nejadi Babadaei
- Department of Molecular Genetics, Faculty of Biological Science, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Samir Haj Bloukh
- Department of Clinical Sciences, College of Pharmacy and Health Sciences, Ajman University, PO Box 346, Ajman, United Arab Emirates; Centre of Medical and Bio-allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
| | - Zehra Edis
- Centre of Medical and Bio-allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates; Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Ajman University, PO Box 346, Ajman, United Arab Emirates
| | - Mesha Saeed
- Precision Medicine in Oncology (PrMiO), Department of Pathology, Erasmus MC Cancer Institute, Erasmus MC, Rotterdam, the Netherlands
| | - Timo L M Ten Hagen
- Precision Medicine in Oncology (PrMiO), Department of Pathology, Erasmus MC Cancer Institute, Erasmus MC, Rotterdam, the Netherlands; Nanomedicine Innovation Center Erasmus (NICE), Erasmus MC, Rotterdam, the Netherlands
| | - Hosein Ahmadi
- Department of Molecular Medicine, Institute of Medical Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Mahsa Ale-Ebrahim
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | | | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, UP 202002, India.
| | - Mojtaba Falahati
- Precision Medicine in Oncology (PrMiO), Department of Pathology, Erasmus MC Cancer Institute, Erasmus MC, Rotterdam, the Netherlands; Nanomedicine Innovation Center Erasmus (NICE), Erasmus MC, Rotterdam, the Netherlands.
| | - Xiaoju Zhang
- Department of Respiratory and Clinical Care Medicine, Henan Provisional People's Hospital, Zhengzhou, China.
| | - Qian Bai
- The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| |
Collapse
|
7
|
Al-Madboly LA. A Novel Triple Combination To Combat Serious Infections with Carbapenem-Resistant Acinetobacter baumannii in a Mouse Pneumonia Model. Microbiol Spectr 2022; 10:e0271021. [PMID: 35975993 PMCID: PMC9603289 DOI: 10.1128/spectrum.02710-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 07/17/2022] [Indexed: 01/04/2023] Open
Abstract
The ongoing crisis of antimicrobial resistance demands novel combinations between antimicrobials and nonantimicrobials to manage infections caused by highly resistant pathogens. This study aimed to evaluate the effect of combining sodium ascorbate and/or apo-transferrin with imipenem, forming double and triple combinations, against 20 multiple-carbapenemase-producing Acinetobacter baumannii strains using the checkerboard test, time-kill assay, and disc diffusion test. The results of the checkerboard assay revealed that all double combinations showed indifference, while only triple combination recorded a synergistic effect (fractional inhibitory concentration index [FICI] < 0.8) in 95% the test isolates. Moreover, the MIC of imipenem (MICimp) was strongly reduced (up to 128-fold reduction) after treatment with the triple combination against highly resistant isolates and reached the susceptible range. The time-kill assay revealed that the triple combination led to a 4-log10 reduction in the CFU at 8 h compared with the initial bacterial count, and no viable count was recorded at 10 h. The mouse pneumonia model showed restoration of lung function and structure, with mild to moderate residual inflammation and moderately congested vessels observed 8 h following administration of the triple rescue therapy. Additionally, normal lungs with normal patent alveoli were detected 72 h following treatment. Accordingly, sodium ascorbate and apo-transferrin are promising adjunct biological agents with the potential to restore the effectiveness of critically essential antibiotics like imipenem, commonly used for the treatment of A. baumannii infections. IMPORTANCE Combination therapy provides a perspective to threat multidrug-resistant (MDR) strains. The present study sheds light on a novel and effective triple combination against carbapenem-resistant A. baumannii. Our in vitro results showed that combining imipenem with apo-transferrin and sodium ascorbate yielded synergism in 95% of test isolates, and this was associated with a marked reduction in imipenem MIC, shifting it below the breakpoint. Furthermore, a bactericidal effect was recorded, with no viable count detected at 10 h. An in vivo murine model of pneumonia was induced to mimic human disease. The triple combination therapy restored lung function and structure, with mild to moderate residual inflammation and moderately congested vessels observed 8 h following the initiation of therapy. Therefore, our findings suggest novel insights about a promising new combination therapy against highly resistant carbapenemase-producing A. baumannii to restore the effectiveness of imipenem.
Collapse
Affiliation(s)
- Lamiaa A. Al-Madboly
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| |
Collapse
|
8
|
In Vitro Activity of Rifabutin and Rifampin against Antibiotic-Resistant Acinetobacter baumannii, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. mSphere 2021; 6:e0092021. [PMID: 34817233 PMCID: PMC8612264 DOI: 10.1128/msphere.00920-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We recently reported that the antimicrobial activity of rifabutin against Acinetobacter baumannii is best modeled by the use of RPMI for in vitro susceptibility testing. Here, we define the effects of medium on the susceptibility and frequency of resistance emergence in a panel of A. baumannii, Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa clinical isolates. Only A. baumannii was hypersusceptible to rifabutin in vitro and in vivo using a Galleria mellonella infection model. In vitro, the frequency of resistance emergence was greater when the bacteria were selected on RPMI versus tryptic soy agar (TSA) or Mueller-Hinton II (MHII) agar plates. However, the frequency of resistance emergence was lower in vivo than in the RPMI in vitro condition. IMPORTANCE Rifabutin has been recently described as a potential adjunctive therapy for antibiotic-resistant A. baumannii infections due to hypersensitivity in iron-depleted media, which may more closely mimic an in vivo environment. Here, we report that this hyperactivity is specific for A. baumannii, rather than being a general effect for other pathogens.
Collapse
|
9
|
Direct Antibiotic Activity of Bacillibactin Broadens the Biocontrol Range of Bacillus amyloliquefaciens MBI600. mSphere 2021; 6:e0037621. [PMID: 34378986 PMCID: PMC8386435 DOI: 10.1128/msphere.00376-21] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus amyloliquefaciens is considered the most successful biological control agent due to its ability to colonize the plant rhizosphere and phyllosphere where it outgrows plant pathogens by competition, antibiosis, and inducing plant defense. Its antimicrobial function is thought to depend on a diverse spectrum of secondary metabolites, including peptides, cyclic lipopeptides, and polyketides, which have been shown to target mostly fungal pathogens. In this study, we isolated and characterized the catecholate siderophore bacillibactin by B. amyloliquefaciens MBI600 under iron-limiting conditions and we further identified its potential antibiotic activity against plant pathogens. Our data show that bacillibactin production restrained in vitro and in planta growth of the nonsusceptible (to MBI600) pathogen Pseudomonas syringae pv. tomato. Notably, it was also related to increased antifungal activity of MBI600. In addition to bacillibactin biosynthesis, iron starvation led to upregulation of specific genes involved in microbial fitness and competition. IMPORTANCE Siderophores have mostly been studied concerning their contribution to the fitness and virulence of bacterial pathogens. In the present work, we isolated and characterized for the first time the siderophore bacillibactin from a commercial bacterial biocontrol agent. We proved that its presence in the culture broth has significant biocontrol activity against nonsusceptible bacterial and fungal phytopathogens. In addition, we suggest that its activity is due to a new mechanism of action, that of direct antibiosis, rather than by competition through iron scavenging. Furthermore, we showed that bacillibactin biosynthesis is coregulated with the transcription of antimicrobial metabolite synthases and fitness regulatory genes that maximize competition capability. Finally, this work highlights that the efficiency and range of existing bacterial biocontrol agents can be improved and broadened via the rational modification of the growth conditions of biocontrol organisms.
Collapse
|
10
|
Characteristics of Quinolone Resistance in Multidrug-Resistant Acinetobacter baumannii Strains Isolated from General Hospitals. Jundishapur J Microbiol 2021. [DOI: 10.5812/jjm.115128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Acinetobacter baumannii is the causative agent in various types of hospital-acquired infections, including respiratory, urinary tract, and wound infections. Objectives: This study investigated the primary mechanisms underlying quinolone resistance in A. baumannii strains, isolated from samples collected from general hospitals. Methods: Ninety-eight strains of A. baumannii were isolated from clinical specimens from general hospitals from 2017 – 2019. Antimicrobial susceptibility, efflux pump inhibition tests, multilocus sequence typing (MLST), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses were conducted on 64 strains, and the blaoxa-51-like gene sequence was detected. Results: In the antimicrobial susceptibility test, 78.1% (n = 50) of the strains exhibited resistance to ciprofloxacin, a quinolone antibiotic, and 57.8% (n = 37) strains were multidrug resistant (MDR). For 18 strains, the minimum inhibitory concentration of ciprofloxacin reduced in presence of an efflux pump inhibitor. Sequence analysis revealed that in 50 strains of A. baumannii, the codon for serine (TCA) in gyrA was replaced by that for leucine (TTA), whereas in 43 strains, the codon for serine (TCG) in parC was replaced by that for leucine (TTG). Multilocus sequence typing analysis confirmed 18 sequence types, and allelic number analysis showed the presence of nine gyrB alleles, with gyrB3 showing the highest frequency (62.5%). Conclusions: The findings of this study will be useful in improving treatment efficiency and preventing the spread of A. baumannii (both MDR and non-MDR strains).
Collapse
|
11
|
Li QQ, Kang OH, Kwon DY. Study on Demethoxycurcumin as a Promising Approach to Reverse Methicillin-Resistance of Staphylococcus aureus. Int J Mol Sci 2021; 22:ijms22073778. [PMID: 33917423 PMCID: PMC8038695 DOI: 10.3390/ijms22073778] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 03/31/2021] [Accepted: 04/03/2021] [Indexed: 12/19/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) has always been a threatening pathogen. Research on phytochemical components that can replace antibiotics with limited efficacy may be an innovative method to solve intractable MRSA infections. The present study was devoted to investigate the antibacterial activity of the natural compound demethoxycurcumin (DMC) against MRSA and explore its possible mechanism for eliminating MRSA. The minimum inhibitory concentrations (MICs) of DMC against MRSA strains was determined by the broth microdilution method, and the results showed that the MIC of DMC was 62.5 μg/mL. The synergistic effects of DMC and antibiotics were investigated by the checkerboard method and the time–kill assay. The ATP synthase inhibitors were employed to block the metabolic ability of bacteria to explore their synergistic effect on the antibacterial ability of DMC. In addition, western blot analysis and qRT-PCR were performed to detect the proteins and genes related to drug resistance and S. aureus exotoxins. As results, DMC hindered the translation of penicillin-binding protein 2a (PBP2a) and staphylococcal enterotoxin and reduced the transcription of related genes. This study provides experimental evidences that DMC has the potential to be a candidate substance for the treatment of MRSA infections.
Collapse
Affiliation(s)
| | - Ok-Hwa Kang
- Correspondence: (O.-H.K.); (D.-Y.K.); Tel.: +82-63-850-6802 (O.-H.K. & D.-Y.K.)
| | - Dong-Yeul Kwon
- Correspondence: (O.-H.K.); (D.-Y.K.); Tel.: +82-63-850-6802 (O.-H.K. & D.-Y.K.)
| |
Collapse
|
12
|
Vinuesa V, McConnell MJ. Recent Advances in Iron Chelation and Gallium-Based Therapies for Antibiotic Resistant Bacterial Infections. Int J Mol Sci 2021; 22:2876. [PMID: 33809032 PMCID: PMC8000330 DOI: 10.3390/ijms22062876] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/04/2021] [Accepted: 03/09/2021] [Indexed: 02/07/2023] Open
Abstract
Iron is essential for multiple bacterial processes and is thus required for host colonization and infection. The antimicrobial activity of multiple iron chelators and gallium-based therapies against different bacterial species has been characterized in preclinical studies. In this review, we provide a synthesis of studies characterizing the antimicrobial activity of the major classes of iron chelators (hydroxamates, aminocarboxylates and hydroxypyridinones) and gallium compounds. Special emphasis is placed on recent in-vitro and in-vivo studies with the novel iron chelator DIBI. Limitations associated with iron chelation and gallium-based therapies are presented, with emphasis on limitations of preclinical models, lack of understanding regarding mechanisms of action, and potential host toxicity. Collectively, these studies demonstrate potential for iron chelators and gallium to be used as antimicrobial agents, particularly in combination with existing antibiotics. Additional studies are needed in order to characterize the activity of these compounds under physiologic conditions and address potential limitations associated with their clinical use as antimicrobial agents.
Collapse
Affiliation(s)
| | - Michael J. McConnell
- Intrahospital Infections Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, 28220 Madrid, Spain;
| |
Collapse
|
13
|
Kontoghiorghes GJ, Kontoghiorghe CN. Iron and Chelation in Biochemistry and Medicine: New Approaches to Controlling Iron Metabolism and Treating Related Diseases. Cells 2020; 9:E1456. [PMID: 32545424 PMCID: PMC7349684 DOI: 10.3390/cells9061456] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/04/2020] [Accepted: 06/05/2020] [Indexed: 02/07/2023] Open
Abstract
Iron is essential for all living organisms. Many iron-containing proteins and metabolic pathways play a key role in almost all cellular and physiological functions. The diversity of the activity and function of iron and its associated pathologies is based on bond formation with adjacent ligands and the overall structure of the iron complex in proteins or with other biomolecules. The control of the metabolic pathways of iron absorption, utilization, recycling and excretion by iron-containing proteins ensures normal biologic and physiological activity. Abnormalities in iron-containing proteins, iron metabolic pathways and also other associated processes can lead to an array of diseases. These include iron deficiency, which affects more than a quarter of the world's population; hemoglobinopathies, which are the most common of the genetic disorders and idiopathic hemochromatosis. Iron is the most common catalyst of free radical production and oxidative stress which are implicated in tissue damage in most pathologic conditions, cancer initiation and progression, neurodegeneration and many other diseases. The interaction of iron and iron-containing proteins with dietary and xenobiotic molecules, including drugs, may affect iron metabolic and disease processes. Deferiprone, deferoxamine, deferasirox and other chelating drugs can offer therapeutic solutions for most diseases associated with iron metabolism including iron overload and deficiency, neurodegeneration and cancer, the detoxification of xenobiotic metals and most diseases associated with free radical pathology.
Collapse
Affiliation(s)
- George J. Kontoghiorghes
- Postgraduate Research Institute of Science, Technology, Environment and Medicine, CY-3021 Limassol, Cyprus;
| | | |
Collapse
|