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Abdulrehman T, Qadri S, Haik Y, Sultan A, Skariah S, Kumar S, Mendoza Z, Yadav KK, Titus A, Khader S. Advances in the targeted theragnostics of osteomyelitis caused by Staphylococcus aureus. Arch Microbiol 2024; 206:288. [PMID: 38834761 DOI: 10.1007/s00203-024-04015-2] [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: 03/31/2024] [Revised: 05/14/2024] [Accepted: 05/20/2024] [Indexed: 06/06/2024]
Abstract
Bone infections caused by Staphylococcus aureus may lead to an inflammatory condition called osteomyelitis, which results in progressive bone loss. Biofilm formation, intracellular survival, and the ability of S. aureus to evade the immune response result in recurrent and persistent infections that present significant challenges in treating osteomyelitis. Moreover, people with diabetes are prone to osteomyelitis due to their compromised immune system, and in life-threatening cases, this may lead to amputation of the affected limbs. In most cases, bone infections are localized; thus, early detection and targeted therapy may prove fruitful in treating S. aureus-related bone infections and preventing the spread of the infection. Specific S. aureus components or overexpressed tissue biomarkers in bone infections could be targeted to deliver active therapeutics, thereby reducing drug dosage and systemic toxicity. Compounds like peptides and antibodies can specifically bind to S. aureus or overexpressed disease markers and combining these with therapeutics or imaging agents can facilitate targeted delivery to the site of infection. The effectiveness of photodynamic therapy and hyperthermia therapy can be increased by the addition of targeting molecules to these therapies enabling site-specific therapy delivery. Strategies like host-directed therapy focus on modulating the host immune mechanisms or signaling pathways utilized by S. aureus for therapeutic efficacy. Targeted therapeutic strategies in conjunction with standard surgical care could be potential treatment strategies for S. aureus-associated osteomyelitis to overcome antibiotic resistance and disease recurrence. This review paper presents information about the targeting strategies and agents for the therapy and diagnostic imaging of S. aureus bone infections.
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Affiliation(s)
- Tahir Abdulrehman
- eHealth Program, DeGroote School of Business, McMaster University, Hamilton, ON, Canada
- Health Policy, Management and Informatics, Allied Health, Credit Valley Hospital, Mississauga, ON, Canada
| | - Shahnaz Qadri
- School of Pharmacy, Texas A&M University, Kingsville, USA.
| | - Yousef Haik
- Department of Mechanical & Nuclear Engineering, University of Sharjah, Sharjah, UAE.
| | - Ali Sultan
- Department of Immunology & Microbiology, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Sini Skariah
- Department of Immunology & Microbiology, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Shourya Kumar
- School of Engineering Medicine, Texas A&M University, Houston, TX, USA
| | - Zachary Mendoza
- School of Engineering Medicine, Texas A&M University, Houston, TX, USA
| | - Kamlesh K Yadav
- School of Engineering Medicine, Texas A&M University, Houston, TX, USA
| | - Anoop Titus
- Department of Preventive Cardiology, Houston Methodist, Houston, TX, USA
| | - Shameer Khader
- School of Public Health, Faculty of Medicine, Imperial College London, London, UK
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van den Biggelaar RHGA, Walburg KV, van den Eeden SJF, van Doorn CLR, Meiler E, de Ries AS, Meijer AH, Ottenhoff THM, Saris A. Identification of kinase modulators as host-directed therapeutics against intracellular methicillin-resistant Staphylococcus aureus. Front Cell Infect Microbiol 2024; 14:1367938. [PMID: 38590439 PMCID: PMC10999543 DOI: 10.3389/fcimb.2024.1367938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 03/11/2024] [Indexed: 04/10/2024] Open
Abstract
The increasing prevalence of antimicrobial-resistant Staphylococcus aureus strains, especially methicillin-resistant S. aureus (MRSA), poses a threat to successful antibiotic treatment. Unsuccessful attempts to develop a vaccine and rising resistance to last-resort antibiotics urge the need for alternative treatments. Host-directed therapy (HDT) targeting critical intracellular stages of S. aureus emerges as a promising alternative, potentially acting synergistically with antibiotics and reducing the risk of de novo drug resistance. We assessed 201 ATP-competitive kinase inhibitors from Published Kinase Inhibitor Sets (PKIS1 and PKIS2) against intracellular MRSA. Seventeen hit compounds were identified, of which the two most effective and well-tolerated hit compounds (i.e., GW633459A and GW296115X) were selected for further analysis. The compounds did not affect planktonic bacterial cultures, while they were active in a range of human cell lines of cervical, skin, lung, breast and monocyte origin, confirming their host-directed mechanisms. GW633459A, structurally related to lapatinib, exhibited an HDT effect on intracellular MRSA independently of its known human epidermal growth factor receptor (EGFR)/(HER) kinase family targets. GW296115X activated adenosine monophosphate-activated protein kinase (AMPK), thereby enhancing bacterial degradation via autophagy. Finally, GW296115X not only reduced MRSA growth in human cells but also improved the survival rates of MRSA-infected zebrafish embryos, highlighting its potential as HDT.
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Affiliation(s)
- Robin H. G. A. van den Biggelaar
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | - Kimberley V. Walburg
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Susan J. F. van den Eeden
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Cassandra L. R. van Doorn
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Eugenia Meiler
- Global Health Medicines R&D, GlaxoSmithKline, Tres Cantos, Spain
| | - Alex S. de Ries
- Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | | | - Tom H. M. Ottenhoff
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Anno Saris
- Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
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Winstel V, Abt ER, Le TM, Radu CG. Targeting host deoxycytidine kinase mitigates Staphylococcus aureus abscess formation. eLife 2024; 12:RP91157. [PMID: 38512723 PMCID: PMC10957174 DOI: 10.7554/elife.91157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024] Open
Abstract
Host-directed therapy (HDT) is an emerging approach to overcome antimicrobial resistance in pathogenic microorganisms. Specifically, HDT targets host-encoded factors required for pathogen replication and survival without interfering with microbial growth or metabolism, thereby eliminating the risk of resistance development. By applying HDT and a drug repurposing approach, we demonstrate that (R)-DI-87, a clinical-stage anticancer drug and potent inhibitor of mammalian deoxycytidine kinase (dCK), mitigates Staphylococcus aureus abscess formation in organ tissues upon invasive bloodstream infection. Mechanistically, (R)-DI-87 shields phagocytes from staphylococcal death-effector deoxyribonucleosides that target dCK and the mammalian purine salvage pathway-apoptosis axis. In this manner, (R)-DI-87-mediated protection of immune cells amplifies macrophage infiltration into deep-seated abscesses, a phenomenon coupled with enhanced pathogen control, ameliorated immunopathology, and reduced disease severity. Thus, pharmaceutical blockade of dCK represents an advanced anti-infective intervention strategy against which staphylococci cannot develop resistance and may help to fight fatal infectious diseases in hospitalized patients.
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Affiliation(s)
- Volker Winstel
- Research Group Pathogenesis of Bacterial Infections; TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Hannover Medical School and the Helmholtz Centre for Infection ResearchHannoverGermany
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical SchoolHannoverGermany
| | - Evan R Abt
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLALos AngelesUnited States
| | - Thuc M Le
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLALos AngelesUnited States
| | - Caius G Radu
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLALos AngelesUnited States
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4
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Winstel V, Abt ER, Le TM, Radu CG. Targeting host deoxycytidine kinase mitigates Staphylococcus aureus abscess formation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.18.553822. [PMID: 37645972 PMCID: PMC10462150 DOI: 10.1101/2023.08.18.553822] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Host-directed therapy (HDT) is an emerging approach to overcome antimicrobial resistance in pathogenic microorganisms. Specifically, HDT targets host-encoded factors required for pathogen replication and survival without interfering with microbial growth or metabolism, thereby eliminating the risk of resistance development. By applying HDT and a drug repurposing approach, we demonstrate that (R)-DI-87, a clinical-stage anti-cancer drug and potent inhibitor of mammalian deoxycytidine kinase (dCK), mitigates Staphylococcus aureus abscess formation in organ tissues upon invasive bloodstream infection. Mechanistically, (R)-DI-87 shields phagocytes from staphylococcal death-effector deoxyribonucleosides that target dCK and the mammalian purine salvage pathway-apoptosis axis. In this manner, (R)-DI-87-mediated protection of immune cells amplifies macrophage infiltration into deep-seated abscesses, a phenomenon coupled with enhanced pathogen control, ameliorated immunopathology, and reduced disease severity. Thus, pharmaceutical blockade of dCK represents an advanced anti-infective intervention strategy against which staphylococci cannot develop resistance and may help to fight fatal infectious diseases in hospitalized patients.
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Affiliation(s)
- Volker Winstel
- Research Group Pathogenesis of Bacterial Infections; TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Hannover Medical School and the Helmholtz Centre for Infection Research, Hannover, Germany
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Evan R. Abt
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, United States of America
| | - Thuc M. Le
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, United States of America
| | - Caius G. Radu
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, United States of America
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5
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Hsieh RC, Liu R, Burgin DJ, Otto M. Understanding mechanisms of virulence in MRSA: implications for antivirulence treatment strategies. Expert Rev Anti Infect Ther 2023; 21:911-928. [PMID: 37501364 DOI: 10.1080/14787210.2023.2242585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 07/26/2023] [Indexed: 07/29/2023]
Abstract
INTRODUCTION Methicillin-resistant Staphylococcus aureus (MRSA) is a widespread pathogen, often causing recurrent and deadly infections in the hospital and community. Many S. aureus virulence factors have been suggested as potential targets for antivirulence therapy to decrease the threat of diminishing antibiotic availability. Antivirulence methods hold promise due to their adjunctive and prophylactic potential and decreased risk for selective pressure. AREAS COVERED This review describes the dominant virulence mechanisms exerted by MRSA and antivirulence therapeutics that are currently undergoing testing in clinical or preclinical stages. We also discuss the advantages and downsides of several investigational antivirulence approaches, including the targeting of bacterial transporters, host-directed therapy, and quorum-sensing inhibitors. For this review, a systematic search of literature on PubMed, Google Scholar, and Web of Science for relevant search terms was performed in April and May 2023. EXPERT OPINION Vaccine and antibody strategies have failed in clinical trials and could benefit from more basic science-informed approaches. Antivirulence-targeting approaches need to be set up better to meet the requirements of drug development, rather than only providing limited results to provide 'proof-of-principle' translational value of pathogenesis research. Nevertheless, there is great potential of such strategies and potential particular promise for novel probiotic approaches.
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Affiliation(s)
- Roger C Hsieh
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Ryan Liu
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Dylan J Burgin
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases (NIAID), U.S. National Institutes of Health (NIH), Bethesda, Maryland, USA
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Mourenza Á, Lorente-Torres B, Durante E, Llano-Verdeja J, Aparicio JF, Fernández-López A, Gil JA, Mateos LM, Letek M. Understanding microRNAs in the Context of Infection to Find New Treatments against Human Bacterial Pathogens. Antibiotics (Basel) 2022; 11:356. [PMID: 35326819 PMCID: PMC8944844 DOI: 10.3390/antibiotics11030356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/25/2022] [Accepted: 03/04/2022] [Indexed: 02/04/2023] Open
Abstract
The development of RNA-based anti-infectives has gained interest with the successful application of mRNA-based vaccines. Small RNAs are molecules of RNA of <200 nucleotides in length that may control the expression of specific genes. Small RNAs include small interference RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), or microRNAs (miRNAs). Notably, the role of miRNAs on the post-transcriptional regulation of gene expression has been studied in detail in the context of cancer and many other genetic diseases. However, it is also becoming apparent that some human miRNAs possess important antimicrobial roles by silencing host genes essential for the progress of bacterial or viral infections. Therefore, their potential use as novel antimicrobial therapies has gained interest during the last decade. The challenges of the transport and delivery of miRNAs to target cells are important, but recent research with exosomes is overcoming the limitations in RNA-cellular uptake, avoiding their degradation. Therefore, in this review, we have summarised the latest developments in the exosomal delivery of miRNA-based therapies, which may soon be another complementary treatment to pathogen-targeted antibiotics that could help solve the problem caused by multidrug-resistant bacteria.
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Affiliation(s)
- Álvaro Mourenza
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
| | - Blanca Lorente-Torres
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
| | - Elena Durante
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
- L’Università di Urbino Carlo Bo, Via Aurelio Saffi, 2, 61029 Urbino, Italy
| | - Jesús Llano-Verdeja
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
| | - Jesús F. Aparicio
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
| | - Arsenio Fernández-López
- Departamento de Biología Molecular, Área de Biología Celular, Universidad de León, 24071 León, Spain;
- Instituto de Biomedicina (IBIOMED), Universidad de León, 24071 León, Spain
- Neural Therapies SL, Campus de Vegazana s/n, 24071 León, Spain
| | - José A. Gil
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
- Instituto de Biología Molecular, Genómica y Proteómica (INBIOMIC), Universidad de León, 24071 León, Spain
| | - Luis M. Mateos
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
- Instituto de Biología Molecular, Genómica y Proteómica (INBIOMIC), Universidad de León, 24071 León, Spain
| | - Michal Letek
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (B.L.-T.); (E.D.); (J.L.-V.); (J.F.A.); (J.A.G.)
- Instituto de Desarrollo Ganadero y Sanidad Animal (INDEGSAL), Universidad de León, 24071 León, Spain
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Kember M, Grandy S, Raudonis R, Cheng Z. Non-Canonical Host Intracellular Niche Links to New Antimicrobial Resistance Mechanism. Pathogens 2022; 11:pathogens11020220. [PMID: 35215166 PMCID: PMC8876822 DOI: 10.3390/pathogens11020220] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/03/2022] [Accepted: 02/05/2022] [Indexed: 12/04/2022] Open
Abstract
Globally, infectious diseases are one of the leading causes of death among people of all ages. The development of antimicrobials to treat infectious diseases has been one of the most significant advances in medical history. Alarmingly, antimicrobial resistance is a widespread phenomenon that will, without intervention, make currently treatable infections once again deadly. In an era of widespread antimicrobial resistance, there is a constant and pressing need to develop new antibacterial drugs. Unraveling the underlying resistance mechanisms is critical to fight this crisis. In this review, we summarize some emerging evidence of the non-canonical intracellular life cycle of two priority antimicrobial-resistant bacterial pathogens: Pseudomonas aeruginosa and Staphylococcus aureus. The bacterial factors that modulate this unique intracellular niche and its implications in contributing to resistance are discussed. We then briefly discuss some recent research that focused on the promises of boosting host immunity as a combination therapy with antimicrobials to eradicate these two particular pathogens. Finally, we summarize the importance of various strategies, including surveillance and vaccines, in mitigating the impacts of antimicrobial resistance in general.
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Liu X, Wu Y, Mao C, Shen J, Zhu K. Host-acting antibacterial compounds combat cytosolic bacteria. Trends Microbiol 2022; 30:761-777. [DOI: 10.1016/j.tim.2022.01.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 12/22/2021] [Accepted: 01/12/2022] [Indexed: 01/25/2023]
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9
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Moreno C, Muñoz C, Terol MJ, Hernández-Rivas JÁ, Villanueva M. Restoration of the immune function as a complementary strategy to treat Chronic Lymphocytic Leukemia effectively. J Exp Clin Cancer Res 2021; 40:321. [PMID: 34654437 PMCID: PMC8517318 DOI: 10.1186/s13046-021-02115-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 09/24/2021] [Indexed: 12/02/2022] Open
Abstract
Chronic Lymphocytic Leukemia (CLL) is a hematological malignancy characterized by uncontrolled proliferation of B-cells and severe immune dysfunction. Chemo(immuno)therapies (CIT) have traditionally aimed to reduce tumor burden without fully understanding their effects on the immune system. As a consequence, CIT are usually associated with higher risk of infections, secondary neoplasms and autoimmune disorders. A better understanding of the biology of the disease has led to the development of therapeutic strategies which not only act against malignant B-cells but also reactivate and enhance the patient's own anti-tumor immune response. Here, we review the current understanding of the underlying interplay between the malignant cells and non-malignant immune cells that may promote tumor survival and proliferation. In addition, we review the available evidence on how different treatment options for CLL including CIT regimens, small molecular inhibitors (i.e, BTK inhibitors, PI3K inhibitors, BCL-2 inhibitors) and T-cell therapies, affect the immune system and their clinical consequences. Finally, we propose that a dual therapeutic approach, acting directly against malignant B-cells and restoring the immune function is clinically relevant and should be considered when developing future strategies to treat patients with CLL.
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Affiliation(s)
| | - Cecilia Muñoz
- Hospital Universitario de la Princesa, Madrid, Spain
| | | | - José-Ángel Hernández-Rivas
- Hospital Universitario Infanta Leonor, Universidad Complutense de Madrid, Madrid, Spain.
- Servicio de Hematología y Hemoterapia, Hospital Universitario Infanta Leonor, Departamento de Medicina, Universidad Complutense de Madrid, Madrid, España.
- , C/ Gran Vía del Este 80, 28031, Madrid, Spain.
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10
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Xiao Y, Zhang TS, Li YH, Liu CF, Yang SJ, Zeng LT, Huang SH, Deng XY, Peng L. Memantine Promotes Bactericidal Effect of Neutrophils Against Infection with Pseudomonas aeruginosa and Its Drug-Resistant Strain, by Improving Reactive Oxygen Species Generation. Microb Drug Resist 2021; 28:7-17. [PMID: 34357802 DOI: 10.1089/mdr.2020.0511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen, which usually presents multiple antibiotic resistance. Host-directed therapy involves modulating the host defense system and the interplay between innate and adaptive immunity is a new strategy for designing anti-infection drugs. Memantine (MEM), a drug used to treat Alzheimer's disease, has a good inhibitory effect on neonatal mice with Escherichia coli-associated bacteremia and meningitis; however, the inhibitory effect and mechanisms of MEM against P. aeruginosa infection remain unclear. Here, we investigated whether MEM could inhibit P. aeruginosa infection and explored the potential mechanisms. MEM significantly promoted the bactericidal effect of neutrophils against P. aeruginosa and its drug-resistant strain. The combination index of MEM and amikacin (AMK) was <1. In vivo experiments showed that the bacteremia and inflammation severities in the MEM-treated group were less than those in the untreated group, and the bacterial load in the organs was significantly less than that in the control group. Combining MEM with the reactive oxygen species (ROS) inhibitor, N-acetyl-l-cysteine, weakened the anti-infective effect of MEM. MEM increased the expression of NADPH p67phox and promoted neutrophilic ROS production. Deleting the p67phox gene significantly weakened the effects of MEM on ROS generation and improving bactericidal effect of neutrophils. In conclusion, MEM promoted the bactericidal effect of neutrophils against P. aeruginosa and its drug-resistant strain, and had a synergistic antibacterial effect when combined with AMK. MEM may exert its anti-infective effects by promoting neutrophilic bactericidal activity via increasing the expression level of p67phox and further stimulating ROS generation.
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Affiliation(s)
- Yi Xiao
- Guangzhou Key Laboratory of Enhanced Recovery After Abdominal Surgery, Department of Clinical Laboratory, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Tie-Song Zhang
- Kunming Key Laboratory of Children Infection and Immunity, Yunnan Institute of Pediatrics, Kunming Children's Hospital, Kunming, China
| | - Ying-Hua Li
- Gynecologic Oncology Ward III, Hunan Cancer Hospital, Changsha, China
| | - Chen-Fei Liu
- Guangzhou Key Laboratory of Enhanced Recovery After Abdominal Surgery, Department of Clinical Laboratory, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Shao-Jie Yang
- Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Diseases, Southern Medical University, Guangzhou, China
| | - Li-Ting Zeng
- Guangzhou Key Laboratory of Enhanced Recovery After Abdominal Surgery, Department of Clinical Laboratory, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Sheng-He Huang
- Kunming Key Laboratory of Children Infection and Immunity, Yunnan Institute of Pediatrics, Kunming Children's Hospital, Kunming, China.,Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Diseases, Southern Medical University, Guangzhou, China.,Department of Pediatrics, Saban Research Institute, University of Southern California, Children's Hospital Los Angeles, Los Angeles, California, USA
| | - Xiao-Yan Deng
- KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou, China
| | - Liang Peng
- Guangzhou Key Laboratory of Enhanced Recovery After Abdominal Surgery, Department of Clinical Laboratory, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou, China
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11
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Vozza EG, Mulcahy ME, McLoughlin RM. Making the Most of the Host; Targeting the Autophagy Pathway Facilitates Staphylococcus aureus Intracellular Survival in Neutrophils. Front Immunol 2021; 12:667387. [PMID: 34220813 PMCID: PMC8242348 DOI: 10.3389/fimmu.2021.667387] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 05/28/2021] [Indexed: 12/21/2022] Open
Abstract
The success of Staphylococcus aureus as a human commensal and an opportunistic pathogen relies on its ability to adapt to several niches within the host. The innate immune response plays a key role in protecting the host against S. aureus infection; however, S. aureus adeptness at evading the innate immune system is indisputably evident. The “Trojan horse” theory has been postulated to describe a mechanism by which S. aureus takes advantage of phagocytes as a survival niche within the host to facilitate dissemination of S. aureus to secondary sites during systemic infection. Several studies have determined that S. aureus can parasitize both professional and non-professional phagocytes by manipulating the host autophagy pathway in order to create an intracellular survival niche. Neutrophils represent a critical cell type in S. aureus infection as demonstrated by the increased risk of infection among patients with congenital neutrophil disorders. However, S. aureus has been repeatedly shown to survive intracellularly within neutrophils with evidence now supporting a pathogenic role of host autophagy. By manipulating this pathway, S. aureus can also alter the apoptotic fate of the neutrophil and potentially skew other important signalling pathways for its own gain. Understanding these critical host-pathogen interactions could lead to the development of new host directed therapeutics for the treatment of S. aureus infection by removing its intracellular niche and restoring host bactericidal functions. This review discusses the current findings surrounding intracellular survival of S. aureus within neutrophils, the pathogenic role autophagy plays in this process and considers the therapeutic potential for targeting this immune evasion mechanism.
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Affiliation(s)
- Emilio G Vozza
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Michelle E Mulcahy
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Rachel M McLoughlin
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
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12
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Soe YM, Bedoui S, Stinear TP, Hachani A. Intracellular Staphylococcus aureus and host cell death pathways. Cell Microbiol 2021; 23:e13317. [PMID: 33550697 DOI: 10.1111/cmi.13317] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 12/13/2022]
Abstract
Staphylococcus aureus is a major opportunistic human pathogen that is globally prevalent. Although S. aureus and humans may have co-evolved to the point of commensalism, the bacterium is equipped with virulence factors causing devastating infections. The adoption of an intracellular lifestyle by S. aureus is an important facet of its pathogenesis. Occupying a privileged intracellular compartment permits evasion from the bactericidal actions of host immunity and antibiotics. However, this localization exposes S. aureus to cell-intrinsic processes comprising autophagy, metabolic challenges and clearance mechanisms orchestrated by host programmed cell death pathways (PCDs), including apoptosis, pyroptosis and necroptosis. Mounting evidence suggests that S. aureus deploys pathoadaptive mechanisms that modulate the expression of its virulence factors to prevent elimination through PCD pathways. In this review, we critically analyse the current literature on the interplay between S. aureus virulence factors with the key, intertwined nodes of PCD. We discuss how S. aureus adaptation to the human host plays an essential role in the evasion of PCD, and we consider future directions to study S. aureus-PCD interactions.
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Affiliation(s)
- Ye Mon Soe
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Sammy Bedoui
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Timothy P Stinear
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Abderrahman Hachani
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
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13
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Mourenza Á, Gil JA, Mateos LM, Letek M. Novel Treatments against Mycobacterium tuberculosis Based on Drug Repurposing. Antibiotics (Basel) 2020; 9:E550. [PMID: 32872158 PMCID: PMC7557778 DOI: 10.3390/antibiotics9090550] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/30/2022] Open
Abstract
Tuberculosis is the leading cause of death, worldwide, due to a bacterial pathogen. This respiratory disease is caused by the intracellular pathogen Mycobacterium tuberculosis and produces 1.5 million deaths every year. The incidence of tuberculosis has decreased during the last decade, but the emergence of MultiDrug-Resistant (MDR-TB) and Extensively Drug-Resistant (XDR-TB) strains of M. tuberculosis is generating a new health alarm. Therefore, the development of novel therapies based on repurposed drugs against MDR-TB and XDR-TB have recently gathered significant interest. Recent evidence, focused on the role of host molecular factors on M. tuberculosis intracellular survival, allowed the identification of new host-directed therapies. Interestingly, the mechanism of action of many of these therapies is linked to the activation of autophagy (e.g., nitazoxanide or imatinib) and other well-known molecular pathways such as apoptosis (e.g., cisplatin and calycopterin). Here, we review the latest developments on the identification of novel antimicrobials against tuberculosis (including avermectins, eltrombopag, or fluvastatin), new host-targeting therapies (e.g., corticoids, fosfamatinib or carfilzomib) and the host molecular factors required for a mycobacterial infection that could be promising targets for future drug development.
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Affiliation(s)
- Álvaro Mourenza
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (J.A.G.)
| | - José A. Gil
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (J.A.G.)
- Instituto de Biología Molecular, Genómica y Proteómica (INBIOMIC), Universidad de León, 24071 León, Spain
| | - Luis M. Mateos
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (J.A.G.)
- Instituto de Biología Molecular, Genómica y Proteómica (INBIOMIC), Universidad de León, 24071 León, Spain
| | - Michal Letek
- Departamento de Biología Molecular, Área de Microbiología, Universidad de León, 24071 León, Spain; (Á.M.); (J.A.G.)
- Instituto de Desarrollo Ganadero y Sanidad Animal (INDEGSAL), Universidad de León, 24071 León, Spain
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14
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Meng K, Chen D, Yang F, Zhang A, Tao Y, Qu W, Pan Y, Hao H, Xie S. Intracellular delivery, accumulation, and discrepancy in antibacterial activity of four enrofloxacin-loaded fatty acid solid lipid nanoparticles. Colloids Surf B Biointerfaces 2020; 194:111196. [PMID: 32599504 DOI: 10.1016/j.colsurfb.2020.111196] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/07/2020] [Accepted: 06/13/2020] [Indexed: 01/09/2023]
Abstract
Four fatty acid-solid lipid nanoparticles (SLNs) were formulated and evaluated for intracellular delivery, accumulation, as well as discrepancy in antimicrobial efficacy of their loaded enrofloxacin by using RAW 264.7 cells. The delivery efficacy of enrofloxacin into the macrophages by docosanoic acid SLNs (DAS), octadecanoic acid SLNs (OAS), hexadecanoic acid SLNs (HAS), and tetradecanoic acid SLNs (TAS) were 26.1-29.0, 9.3-10.3, 4.7-5.3 and 4.5-5.0 folds, respectively, compared to free drug when co-incubation for 0.25-4 h. The longer fatty acid prepared nanoparticles loaded enrofloxacin eliminated more slowly and accumulated in the cells for a longer time.The confocal microscopy also demonstrated that higher amount of fatty acid SLNs entered the cells with stronger accumulation performance and less amount SLNs absorbed on the cytomembrane as the carbon chain of fatty acids increased. The bactericidal activity of the four fatty acid SLNs against intracellular Salmonella CVCC541 significantly enhanced compared to the free enrofloxacin. These results revealed that fatty acid SLNs, especially docosanoic acid nanoparticles, might be effective nanocarriers to ferry enrofloxacin or other lipid soluble drugs into cells for intracellular bacterial infection treatment.
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Affiliation(s)
- Kuiyu Meng
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Dongmei Chen
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China; MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Fei Yang
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Aoxue Zhang
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Yanfei Tao
- MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Wei Qu
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Yuanhu Pan
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Haihong Hao
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Shuyu Xie
- National Reference Laboratory of Veterinary Drug Residues (HZAU), Huazhong Agricultural University, Wuhan, Hubei 430070, China.
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15
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Sámano-Sánchez H, Gibson TJ. Mimicry of Short Linear Motifs by Bacterial Pathogens: A Drugging Opportunity. Trends Biochem Sci 2020; 45:526-544. [PMID: 32413327 DOI: 10.1016/j.tibs.2020.03.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 02/25/2020] [Accepted: 03/03/2020] [Indexed: 12/11/2022]
Abstract
Bacterial pathogens have developed complex strategies to successfully survive and proliferate within their hosts. Throughout the infection cycle, direct interaction with host cells occurs. Many bacteria have been found to secrete proteins, such as effectors and toxins, directly into the host cell with the potential to interfere with cell regulatory processes, either enzymatically or through protein-protein interactions (PPIs). Short linear motifs (SLiMs) are abundant peptide modules in cell signaling proteins. Here, we cover the reported examples of eukaryotic-like SLiM mimicry being used by pathogenic bacteria to hijack host cell machinery and discuss how drugs targeting SLiM-regulated cell signaling networks are being evaluated for interference with bacterial infections. This emerging anti-infective opportunity may become an essential contributor to antibiotic replacement strategies.
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Affiliation(s)
- Hugo Sámano-Sánchez
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany; Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, 69120 Heidelberg, Germany
| | - Toby J Gibson
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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16
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Host-Targeted Therapeutics against Multidrug Resistant Intracellular Staphylococcus aureus. Antibiotics (Basel) 2019; 8:antibiotics8040241. [PMID: 31795127 PMCID: PMC6963206 DOI: 10.3390/antibiotics8040241] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 12/14/2022] Open
Abstract
Staphylococcus aureus is a facultative intracellular pathogen that invades and replicates within many types of human cells. S. aureus has shown to rapidly overcome traditional antibiotherapy by developing multidrug resistance. Furthermore, intracellular S. aureus is protected from the last-resort antibiotics—vancomycin, daptomycin, and linezolid—as they are unable to achieve plasma concentrations sufficient for intracellular killing. Therefore, there is an urgent need to develop novel anti-infective therapies against S. aureus infections. Here, we review the current state of the field and highlight the exploitation of host-directed approaches as a promising strategy going forward.
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17
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Kumar R, Harilal S, Gupta SV, Jose J, Thomas Parambi DG, Uddin MS, Shah MA, Mathew B. Exploring the new horizons of drug repurposing: A vital tool for turning hard work into smart work. Eur J Med Chem 2019; 182:111602. [PMID: 31421629 PMCID: PMC7127402 DOI: 10.1016/j.ejmech.2019.111602] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/07/2019] [Accepted: 08/07/2019] [Indexed: 02/07/2023]
Abstract
Drug discovery and development are long and financially taxing processes. On an average it takes 12-15 years and costs 1.2 billion USD for successful drug discovery and approval for clinical use. Many lead molecules are not developed further and their potential is not tapped to the fullest due to lack of resources or time constraints. In order for a drug to be approved by FDA for clinical use, it must have excellent therapeutic potential in the desired area of target with minimal toxicities as supported by both pre-clinical and clinical studies. The targeted clinical evaluations fail to explore other potential therapeutic applications of the candidate drug. Drug repurposing or repositioning is a fast and relatively cheap alternative to the lengthy and expensive de novo drug discovery and development. Drug repositioning utilizes the already available clinical trials data for toxicity and adverse effects, at the same time explores the drug's therapeutic potential for a different disease. This review addresses recent developments and future scope of drug repositioning strategy.
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Affiliation(s)
- Rajesh Kumar
- Department of Pharmacy, Kerala University of Health Sciences, Thrissur, Kerala, India
| | - Seetha Harilal
- Department of Pharmacy, Kerala University of Health Sciences, Thrissur, Kerala, India
| | - Sheeba Varghese Gupta
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, 33612, USA
| | - Jobin Jose
- Department of Pharmaceutics, NGSM Institute of Pharmaceutical Science, NITTE Deemed to be University, Manglore, 575018, India
| | - Della Grace Thomas Parambi
- Department of Pharmaceutical Chemistry, College of Pharmacy, Jouf University, Sakaka, Al Jouf, 2014, Saudi Arabia
| | - Md Sahab Uddin
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh; Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Muhammad Ajmal Shah
- Department of Pharmacogonosy, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Bijo Mathew
- Division of Drug Design and Medicinal Chemistry Research Lab, Department of Pharmaceutical Chemistry, Ahalia School of Pharmacy, Palakkad, 678557, Kerala, India.
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18
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Bravo-Santano N, Capilla-Lasheras P, Mateos LM, Calle Y, Behrends V, Letek M. Identification of novel targets for host-directed therapeutics against intracellular Staphylococcus aureus. Sci Rep 2019; 9:15435. [PMID: 31659191 PMCID: PMC6817851 DOI: 10.1038/s41598-019-51894-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 10/09/2019] [Indexed: 01/26/2023] Open
Abstract
During patient colonization, Staphylococcus aureus is able to invade and proliferate within human cells to evade the immune system and last resort drugs such as vancomycin. Hijacking specific host molecular factors and/or pathways is necessary for pathogens to successfully establish an intracellular infection. In this study, we employed an unbiased shRNA screening coupled with ultra-fast sequencing to screen 16,000 human genes during S. aureus infection and we identified several host genes important for this intracellular pathogen. In addition, we interrogated our screening results to find novel host-targeted therapeutics against intracellular S. aureus. We found that silencing the human gene TRAM2 resulted in a significant reduction of intracellular bacterial load while host cell viability was restored, showing its importance during intracellular infection. Furthermore, TRAM2 is an interactive partner of the endoplasmic reticulum SERCA pumps and treatment with the SERCA-inhibitor Thapsigargin halted intracellular MRSA survival. Our results suggest that Thapsigargin could be repurposed to tackle S. aureus host cell infection in combination with conventional antibiotics.
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Affiliation(s)
| | | | - Luis M Mateos
- Department of Molecular Biology, Area of Microbiology, University of León, León, Spain
| | - Yolanda Calle
- Health Sciences Research Centre, University of Roehampton, London, UK
| | - Volker Behrends
- Health Sciences Research Centre, University of Roehampton, London, UK.
| | - Michal Letek
- Health Sciences Research Centre, University of Roehampton, London, UK.
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19
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Bravo-Santano N, Ellis JK, Calle Y, Keun HC, Behrends V, Letek M. Intracellular Staphylococcus aureus Elicits the Production of Host Very Long-Chain Saturated Fatty Acids with Antimicrobial Activity. Metabolites 2019; 9:metabo9070148. [PMID: 31330837 PMCID: PMC6680556 DOI: 10.3390/metabo9070148] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/10/2019] [Accepted: 07/17/2019] [Indexed: 12/14/2022] Open
Abstract
As a facultative intracellular pathogen, Staphylococcus aureus is able to invade and proliferate within many types of mammalian cells. Intracellular bacterial replication relies on host nutrient supplies and, therefore, cell metabolism is closely bound to intracellular infection. Here, we investigated how S. aureus invasion affects the host membrane-bound fatty acids. We quantified the relative levels of fatty acids and their labelling pattern after intracellular infection by gas chromatography-mass spectrometry (GC-MS). Interestingly, we observed that the levels of three host fatty acids—docosanoic, eicosanoic and palmitic acids—were significantly increased in response to intracellular S. aureus infection. Accordingly, labelling carbon distribution was also affected in infected cells, in comparison to the uninfected control. In addition, treatment of HeLa cells with these three fatty acids showed a cytoprotective role by directly reducing S. aureus growth.
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Affiliation(s)
| | - James K Ellis
- Division of Cancer, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London W12 0HS, UK
| | - Yolanda Calle
- Health Sciences Research Centre, University of Roehampton, London SW15 4JD, UK
| | - Hector C Keun
- Division of Cancer, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London W12 0HS, UK
| | - Volker Behrends
- Health Sciences Research Centre, University of Roehampton, London SW15 4JD, UK.
| | - Michal Letek
- Health Sciences Research Centre, University of Roehampton, London SW15 4JD, UK.
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