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Lakhal-Littleton S, Cleland JGF. Iron deficiency and supplementation in heart failure. Nat Rev Cardiol 2024; 21:463-486. [PMID: 38326440 DOI: 10.1038/s41569-024-00988-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/08/2024] [Indexed: 02/09/2024]
Abstract
Non-anaemic iron deficiency (NAID) is a strategic target in cardiovascular medicine because of its association with a range of adverse effects in various conditions. Endeavours to tackle NAID in heart failure have yielded mixed results, exposing knowledge gaps in how best to define 'iron deficiency' and the handling of iron therapies by the body. To address these gaps, we harness the latest understanding of the mechanisms of iron homeostasis outside the erythron and integrate clinical and preclinical lines of evidence. The emerging picture is that current definitions of iron deficiency do not assimilate the multiple influences at play in patients with heart failure and, consequently, fail to identify those with a truly unmet need for iron. Additionally, current iron supplementation therapies benefit only certain patients with heart failure, reflecting differences in the nature of the unmet need for iron and the modifying effects of anaemia and inflammation on the handling of iron therapies by the body. Building on these insights, we identify untapped opportunities in the management of NAID, including the refinement of current approaches and the development of novel strategies. Lessons learned from NAID in cardiovascular disease could ultimately translate into benefits for patients with other chronic conditions such as chronic kidney disease, chronic obstructive pulmonary disease and cancer.
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Affiliation(s)
| | - John G F Cleland
- British Heart Foundation Centre of Research Excellence, School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, UK
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2
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Lin Q, Huang E, Fan K, Zhang Z, Shangguan H, Zhang W, Fang W, Ou Q, Liu X. Cerebrospinal Fluid Neutrophil Gelatinase-Associated Lipocalin as a Novel Biomarker for Postneurosurgical Bacterial Meningitis: A Prospective Observational Cohort Study. Neurosurgery 2024:00006123-990000000-01205. [PMID: 38856216 DOI: 10.1227/neu.0000000000003021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 04/08/2024] [Indexed: 06/11/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Postneurosurgical bacterial meningitis (PNBM) was a significant clinical challenge, as early identification remains difficult. This study aimed to explore the potential of neutrophil gelatinase-associated lipocalin (NGAL) as a novel biomarker for the early diagnosis of PNBM in patients who have undergone neurosurgery. METHODS A total of 436 postneurosurgical adult patients were enrolled in this study. Clinical information, cerebrospinal fluid (CSF), and blood samples were collected. After the screening, the remaining 267 patients were divided into the PNBM and non-PNBM groups, and measured CSF and serum NGAL levels to determine the diagnostic utility of PNBM. Subsequently, patients with PNBM were categorized into gram-positive and gram-negative bacterial infection groups to assess the effectiveness of CSF NGAL in differentiating between these types of infections. We analyzed the changes in CSF NGAL expression before and after anti-infection treatment in PNBM. Finally, an additional 60 patients were included as an independent validation cohort to further validate the diagnostic performance of CSF NGAL. RESULTS Compared with the non-PNBM group, CSF NGAL was significantly higher in the PNBM group (305.1 [151.6-596.5] vs 58.5 [30.7-105.8] ng/mL; P < .0001). The area under the curve of CSF NGAL for diagnosing PNBM was 0.928 (95% CI: 0.897-0.960), at a threshold of 119.7 ng/mL. However, there was no significant difference in serum NGAL between the 2 groups (142.5 [105.0-248.6] vs 161.9 [126.6-246.6] ng/mL, P = .201). Furthermore, CSF NGAL levels were significantly higher in patients with gram-negative bacterial infections than those with gram-positive bacteria (P = .023). In addition, CSF NGAL levels decrease after treatment compared with the initial stage of infection (P < .0001). Finally, in this validation cohort, the threshold of 119.7 ng/mL CSF NGAL shows good diagnostic performance with a sensitivity and specificity of 90% and 80%, respectively. CONCLUSION CSF NGAL holds promise as a potential biomarker for the diagnosis, early drug selection, and efficacy monitoring of PNBM.
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Affiliation(s)
- Qingwen Lin
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Laboratory Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Clinical Research Center for Clinical Immunology Laboratory Test, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Er Huang
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Laboratory Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Clinical Research Center for Clinical Immunology Laboratory Test, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Kengna Fan
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Laboratory Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Clinical Research Center for Clinical Immunology Laboratory Test, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Zeqin Zhang
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Huangcheng Shangguan
- Department of Neurosurgery, Neurosurgery Research Institute, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Weiqing Zhang
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Laboratory Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Clinical Research Center for Clinical Immunology Laboratory Test, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Wenhua Fang
- Department of Neurosurgery, Neurosurgery Research Institute, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Qishui Ou
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Laboratory Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Clinical Research Center for Clinical Immunology Laboratory Test, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
| | - Xiaofeng Liu
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Department of Laboratory Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
- Fujian Clinical Research Center for Clinical Immunology Laboratory Test, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China
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3
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Arya R, Jit BP, Kumar V, Kim JJ. Exploring the Potential of Exosomes as Biomarkers in Tuberculosis and Other Diseases. Int J Mol Sci 2024; 25:2885. [PMID: 38474139 DOI: 10.3390/ijms25052885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 02/23/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Tuberculosis (TB) is a major cause of morbidity and mortality and remains an important public health issue in developing countries worldwide. The existing methods and techniques available for the diagnosis of TB are based on combinations of laboratory (chemical and biological), radiological, and clinical tests. These methods are sophisticated and laborious and have limitations in terms of sensitivity, specificity, and accuracy. Clinical settings need improved diagnostic biomarkers to accurately detect biological changes due to pathogen invasion and pharmacological responses. Exosomes are membrane-bound vesicles and mediators of intercellular signaling processes that play a significant role in the pathogenesis of various diseases, such as tuberculosis, and can act as promising biomarkers for the monitoring of TB infection. Compared to conventional biomarkers, exosome-derived biomarkers are advantageous because they are easier to detect in different biofluids, are more sensitive and specific, and may be useful in tracking patients' reactions to therapy. This review provides insights into the types of biomarkers, methods of exosome isolation, and roles of the cargo (proteins) present in exosomes isolated from patients through omics studies, such as proteomics. These findings will aid in developing new prognostic and diagnostic biomarkers and could lead to the identification of new therapeutic targets in the clinical setting.
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Affiliation(s)
- Rakesh Arya
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Bimal Prasad Jit
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Vijay Kumar
- Department of Orthopaedic Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jong Joo Kim
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541, Republic of Korea
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Stefanache A, Lungu II, Butnariu IA, Calin G, Gutu C, Marcu C, Grierosu C, Bogdan Goroftei ER, Duceac LD, Dabija MG, Popa F, Damir D. Understanding How Minerals Contribute to Optimal Immune Function. J Immunol Res 2023; 2023:3355733. [PMID: 37946846 PMCID: PMC10632063 DOI: 10.1155/2023/3355733] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/16/2023] [Accepted: 09/09/2023] [Indexed: 11/12/2023] Open
Abstract
Sufficient mineral supply is vital not only for the innate immune system but also for the components of the adaptive immune defense, which encompass defense mechanisms against pathogens and the delicate balance of pro- and anti-inflammatory regulation in the long term. Generally, a well-balanced diet is capable of providing the necessary minerals to support the immune system. Nevertheless, specific vulnerable populations should be cautious about obtaining adequate amounts of minerals such as magnesium, zinc, copper, iron, and selenium. Inadequate levels of these minerals can temporarily impair immune competence and disrupt the long-term regulation of systemic inflammation. Therefore, comprehending the mechanisms and sources of these minerals is crucial. In exceptional circumstances, mineral deficiencies may necessitate supplementation; however, excessive intake of supplements can have adverse effects on the immune system and should be avoided. Consequently, any supplementation should be approved by medical professionals and administered in recommended doses. This review emphasizes the crucial significance of minerals in promoting optimal functioning of the immune system. It investigates the indispensable minerals required for immune system function and the regulation of inflammation. Moreover, it delves into the significance of maintaining an optimized intake of minerals from a nutritional standpoint.
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Affiliation(s)
- Alina Stefanache
- “Grigore T. Popa” University of Medicine and Pharmacy, Iasi 700115, Romania
| | - Ionut-Iulian Lungu
- “Grigore T. Popa” University of Medicine and Pharmacy, Iasi 700115, Romania
| | | | - Gabriela Calin
- Faculty of Dental Medicine, “Apollonia” University of Iasi, 11 Pacurari Street, Iasi 700511, Romania
| | - Cristian Gutu
- Faculty of Medicine and Pharmacy, University Dunarea de Jos, 47 Domneasca Street, Galati 800008, Romania
| | - Constantin Marcu
- Faculty of Medicine and Pharmacy, University Dunarea de Jos, 47 Domneasca Street, Galati 800008, Romania
| | - Carmen Grierosu
- Faculty of Dental Medicine, “Apollonia” University of Iasi, 11 Pacurari Street, Iasi 700511, Romania
| | | | - Letitia-Doina Duceac
- Faculty of Medicine and Pharmacy, University Dunarea de Jos, 47 Domneasca Street, Galati 800008, Romania
| | | | - Florina Popa
- Faculty of Medicine and Pharmacy, University Dunarea de Jos, 47 Domneasca Street, Galati 800008, Romania
| | - Daniela Damir
- “Grigore T. Popa” University of Medicine and Pharmacy, Iasi 700115, Romania
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5
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Zhou Y, Zhou Z, Zheng L, Gong Z, Li Y, Jin Y, Huang Y, Chi M. Urinary Tract Infections Caused by Uropathogenic Escherichia coli: Mechanisms of Infection and Treatment Options. Int J Mol Sci 2023; 24:10537. [PMID: 37445714 DOI: 10.3390/ijms241310537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/15/2023] Open
Abstract
Urinary tract infections (UTIs) are common bacterial infections that represent a severe public health problem. They are often caused by Escherichia coli (E. coli), Klebsiella pneumoniae (K. pneumonia), Proteus mirabilis (P. mirabilis), Enterococcus faecalis (E. faecalis), and Staphylococcus saprophyticus (S. saprophyticus). Among these, uropathogenic E. coli (UPEC) are the most common causative agent in both uncomplicated and complicated UTIs. The adaptive evolution of UPEC has been observed in several ways, including changes in colonization, attachment, invasion, and intracellular replication to invade the urothelium and survive intracellularly. While antibiotic therapy has historically been very successful in controlling UTIs, high recurrence rates and increasing antimicrobial resistance among uropathogens threaten to greatly reduce the efficacy of these treatments. Furthermore, the gradual global emergence of multidrug-resistant UPEC has highlighted the need to further explore its pathogenesis and seek alternative therapeutic and preventative strategies. Therefore, a thorough understanding of the clinical status and pathogenesis of UTIs and the advantages and disadvantages of antibiotics as a conventional treatment option could spark a surge in the search for alternative treatment options, especially vaccines and medicinal plants. Such options targeting multiple pathogenic mechanisms of UPEC are expected to be a focus of UTI management in the future to help combat antibiotic resistance.
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Affiliation(s)
- Yang Zhou
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
- School of Pharmaceutical Sciences, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Zuying Zhou
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
- School of Pharmaceutical Sciences, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Lin Zheng
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
- School of Pharmaceutical Sciences, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Zipeng Gong
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Yueting Li
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Yang Jin
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Yong Huang
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
- School of Pharmaceutical Sciences, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
| | - Mingyan Chi
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
- School of Pharmaceutical Sciences, Guizhou Medical University, 4 Beijing Road, Guiyang 550004, China
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Gao M, Zhao T, Zhang C, Li P, Wang J, Han J, Zhang N, Pang B, Liu S. Ferritinophagy-mediated iron competition in RUTIs: Tug-of-war between UPEC and host. Biomed Pharmacother 2023; 163:114859. [PMID: 37167722 DOI: 10.1016/j.biopha.2023.114859] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/24/2023] [Accepted: 05/06/2023] [Indexed: 05/13/2023] Open
Abstract
Uropathogenic Escherichia coli (UPEC) is the main pathogen of recurrent urinary tract infections (RUTIs). Urinary tract infection is a complicated interaction between UPEC and the host. During infection, UPEC can evade the host's immune response and retain in bladder epithelial cells, which requires adequate nutritional support. Iron is the first necessary trace element in life and a key nutritional factor, making it an important part of the competition between UPEC and the host. On the one hand, UPEC grabs iron to satisfy its reproduction, on the other hand, the host relies on iron to build nutritional immunity defenses against UPEC. Ferritinophagy is a selective autophagy of ferritin mediated by nuclear receptor coactivator 4, which is not only a way for the host to regulate iron metabolism to maintain iron homeostasis, but also a key point of competition between the host and UPEC. Although recent studies have confirmed the role of ferritinophagy in the progression of many diseases, the mechanism of potential interactions between ferritinophagy in UPEC and the host is poorly understood. In this paper, we reviewed the potential mechanisms of ferritinophagy-mediated iron competition in the UPEC-host interactions. This competitive relationship, like a tug-of-war, is a confrontation between the capability of UPEC to capture iron and the host's nutritional immunity defense, which could be the trigger for RUTIs. Therefore, understanding ferritinophagy-mediated iron competition may provide new strategies for exploring effective antibiotic alternative therapies to prevent and treat RUTIs.
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Affiliation(s)
- Mengqi Gao
- Department of Nephrology and Endocrinology, Wangjing Hospital, China Academy of Chinese Medical Sciences, Beijing 100102, China
| | - Tingting Zhao
- Department of Nephrology, Beijing Key Laboratory for Immune-Mediated Inflammatory 9 Diseases, China-Japan Friendship Hospital, Beijing 100029, China
| | - Chuanlong Zhang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China
| | - Ping Li
- Department of Nephrology, Beijing Key Laboratory for Immune-Mediated Inflammatory 9 Diseases, China-Japan Friendship Hospital, Beijing 100029, China
| | - Jiazhe Wang
- Beijing University of Chinese Medicine, Beijing 100029, China
| | - Jiatong Han
- Department of Nephrology and Endocrinology, Wangjing Hospital, China Academy of Chinese Medical Sciences, Beijing 100102, China
| | - Ning Zhang
- Department of Nephrology and Endocrinology, Wangjing Hospital, China Academy of Chinese Medical Sciences, Beijing 100102, China
| | - Bo Pang
- International Medical Department of Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China.
| | - Shiwei Liu
- Department of Nephrology and Endocrinology, Wangjing Hospital, China Academy of Chinese Medical Sciences, Beijing 100102, China.
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7
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Butler D, Ambite I, Wan MLY, Tran TH, Wullt B, Svanborg C. Immunomodulation therapy offers new molecular strategies to treat UTI. Nat Rev Urol 2022; 19:419-437. [PMID: 35732832 PMCID: PMC9214477 DOI: 10.1038/s41585-022-00602-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2022] [Indexed: 12/13/2022]
Abstract
Innovative solutions are needed for the treatment of bacterial infections, and a range of antibacterial molecules have been explored as alternatives to antibiotics. A different approach is to investigate the immune system of the host for new ways of making the antibacterial defence more efficient. However, the immune system has a dual role as protector and cause of disease: in addition to being protective, increasing evidence shows that innate immune responses can become excessive and cause acute symptoms and tissue pathology during infection. This role of innate immunity in disease suggests that the immune system should be targeted therapeutically, to inhibit over-reactivity. The ultimate goal is to develop therapies that selectively attenuate destructive immune response cascades, while augmenting the protective antimicrobial defence but such treatment options have remained underexplored, owing to the molecular proximity of the protective and destructive effects of the immune response. The concept of innate immunomodulation therapy has been developed successfully in urinary tract infections, based on detailed studies of innate immune activation and disease pathogenesis. Effective, disease-specific, immunomodulatory strategies have been developed by targeting specific immune response regulators including key transcription factors. In acute pyelonephritis, targeting interferon regulatory factor 7 using small interfering RNA or treatment with antimicrobial peptide cathelicidin was protective and, in acute cystitis, targeting overactive effector molecules such as IL-1β, MMP7, COX2, cAMP and the pain-sensing receptor NK1R has been successful in vivo. Furthermore, other UTI treatment strategies, such as inhibiting bacterial adhesion and vaccination, have also shown promise. Hyperactivation of innate immunity is a disease determinant in urinary tract infections (UTIs). Modulation of innate immunity has promise as a therapy for UTIs. In this Review, the authors discuss potential mechanisms and immunomodulatory therapeutic strategies in UTIs. Excessive innate immune responses to infection cause symptoms and pathology in acute pyelonephritis and acute cystitis. Innate immunomodulation therapy is, therefore, a realistic option for treating these conditions. Targeting excessive innate immune responses at the level of transcription has been successful in animal models. Innate immunomodulation therapy reduces excessive inflammation and tissue pathology and accelerates bacterial clearance from infected kidneys and bladders in mice. Innate immunomodulation therapy also accelerates the clearance of antibiotic-resistant bacterial strains.
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Affiliation(s)
- Daniel Butler
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Ines Ambite
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Murphy Lam Yim Wan
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Thi Hien Tran
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Björn Wullt
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Catharina Svanborg
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden.
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Ferrous Iron Uptake Is Required for Salmonella to Persist within Vacuoles of Host Cells. Infect Immun 2022; 90:e0014922. [PMID: 35536027 DOI: 10.1128/iai.00149-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Iron is an essential oligoelement that incorporates into proteins as a biocatalyst or electron carrier. The intracellular pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) takes iron as free reduced ferrous cation or as oxidized ferric cation complexed to siderophores or ferrichromes. Deficiencies in ferrous or ferric iron uptake attenuate S. Typhimurium virulence, but how the uptake systems are used in the intracellular environment remains poorly understood. Here, using S. Typhimurium mutants deficient in multiple iron uptake systems, we show that SitABCD and FeoABC, involved in ferrous iron uptake, are central for this pathogen to persist within vacuoles of fibroblasts. Assays at the protein level showed that components of these two uptake systems, SitD and FeoB, are produced at high levels by intravacuolar bacteria. Despite not being essential for viability inside the vacuole, intracellular bacteria also upregulate transporters involved in ferric iron uptake such as IroN, FepA, and CirA. In addition, an unprecedented cleavage at the N-terminal region of FepA was observed as a distinctive feature of nonproliferating intravacuolar bacteria. Collectively, our findings indicate that SitABCD and FeoABC contribute to S. Typhimurium virulence by promoting iron acquisition within the vacuolar compartment.
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9
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Kumar A, Yang T, Chakravorty S, Majumdar A, Nairn BL, Six DA, Marcondes Dos Santos N, Price SL, Lawrenz MB, Actis LA, Marques M, Russo TA, Newton SM, Klebba PE. Fluorescent sensors of siderophores produced by bacterial pathogens. J Biol Chem 2022; 298:101651. [PMID: 35101443 PMCID: PMC8921320 DOI: 10.1016/j.jbc.2022.101651] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/25/2022] Open
Abstract
Siderophores are iron-chelating molecules that solubilize Fe3+ for microbial utilization and facilitate colonization or infection of eukaryotes by liberating host iron for bacterial uptake. By fluorescently labeling membrane receptors and binding proteins, we created 20 sensors that detect, discriminate, and quantify apo- and ferric siderophores. The sensor proteins originated from TonB-dependent ligand-gated porins (LGPs) of Escherichia coli (Fiu, FepA, Cir, FhuA, IutA, BtuB), Klebsiella pneumoniae (IroN, FepA, FyuA), Acinetobacter baumannii (PiuA, FepA, PirA, BauA), Pseudomonas aeruginosa (FepA, FpvA), and Caulobacter crescentus (HutA) from a periplasmic E. coli binding protein (FepB) and from a human serum binding protein (siderocalin). They detected ferric catecholates (enterobactin, degraded enterobactin, glucosylated enterobactin, dihydroxybenzoate, dihydroxybenzoyl serine, cefidericol, MB-1), ferric hydroxamates (ferrichromes, aerobactin), mixed iron complexes (yersiniabactin, acinetobactin, pyoverdine), and porphyrins (hemin, vitamin B12). The sensors defined the specificities and corresponding affinities of the LGPs and binding proteins and monitored ferric siderophore and porphyrin transport by microbial pathogens. We also quantified, for the first time, broad recognition of diverse ferric complexes by some LGPs, as well as monospecificity for a single metal chelate by others. In addition to their primary ferric siderophore ligands, most LGPs bound the corresponding aposiderophore with ∼100-fold lower affinity. These sensors provide insights into ferric siderophore biosynthesis and uptake pathways in free-living, commensal, and pathogenic Gram-negative bacteria.
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Affiliation(s)
- Ashish Kumar
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Taihao Yang
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Somnath Chakravorty
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA; Department of Medicine, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo School of Medicine, Buffalo, New York, USA
| | - Aritri Majumdar
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Brittany L Nairn
- Department of Biological Sciences, Bethel University, St. Paul, Minnesota, USA
| | - David A Six
- Department of Biology, Venatorx Pharmaceuticals, Inc, Malvern, Pennsylvania, USA
| | - Naara Marcondes Dos Santos
- Departamento de Microbiologia, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Sarah L Price
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Matthew B Lawrenz
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Luis A Actis
- Department of Microbiology, Miami University, Oxford, Ohio, USA
| | - Marilis Marques
- Departamento de Microbiologia, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Thomas A Russo
- Department of Medicine, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo School of Medicine, Buffalo, New York, USA
| | - Salete M Newton
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Phillip E Klebba
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA.
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Klebba PE, Newton SMC, Six DA, Kumar A, Yang T, Nairn BL, Munger C, Chakravorty S. Iron Acquisition Systems of Gram-negative Bacterial Pathogens Define TonB-Dependent Pathways to Novel Antibiotics. Chem Rev 2021; 121:5193-5239. [PMID: 33724814 PMCID: PMC8687107 DOI: 10.1021/acs.chemrev.0c01005] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Iron is an indispensable metabolic cofactor in both pro- and eukaryotes, which engenders a natural competition for the metal between bacterial pathogens and their human or animal hosts. Bacteria secrete siderophores that extract Fe3+ from tissues, fluids, cells, and proteins; the ligand gated porins of the Gram-negative bacterial outer membrane actively acquire the resulting ferric siderophores, as well as other iron-containing molecules like heme. Conversely, eukaryotic hosts combat bacterial iron scavenging by sequestering Fe3+ in binding proteins and ferritin. The variety of iron uptake systems in Gram-negative bacterial pathogens illustrates a range of chemical and biochemical mechanisms that facilitate microbial pathogenesis. This document attempts to summarize and understand these processes, to guide discovery of immunological or chemical interventions that may thwart infectious disease.
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Affiliation(s)
- Phillip E Klebba
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Salete M C Newton
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - David A Six
- Venatorx Pharmaceuticals, Inc., 30 Spring Mill Drive, Malvern, Pennsylvania 19355, United States
| | - Ashish Kumar
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Taihao Yang
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Brittany L Nairn
- Department of Biological Sciences, Bethel University, 3900 Bethel Drive, St. Paul, Minnesota 55112, United States
| | - Colton Munger
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Somnath Chakravorty
- Jacobs School of Medicine and Biomedical Sciences, SUNY Buffalo, Buffalo, New York 14203, United States
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11
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Ambite I, Butler D, Wan MLY, Rosenblad T, Tran TH, Chao SM, Svanborg C. Molecular determinants of disease severity in urinary tract infection. Nat Rev Urol 2021; 18:468-486. [PMID: 34131331 PMCID: PMC8204302 DOI: 10.1038/s41585-021-00477-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/07/2021] [Indexed: 02/06/2023]
Abstract
The most common and lethal bacterial pathogens have co-evolved with the host. Pathogens are the aggressors, and the host immune system is responsible for the defence. However, immune responses can also become destructive, and excessive innate immune activation is a major cause of infection-associated morbidity, exemplified by symptomatic urinary tract infections (UTIs), which are caused, in part, by excessive innate immune activation. Severe kidney infections (acute pyelonephritis) are a major cause of morbidity and mortality, and painful infections of the urinary bladder (acute cystitis) can become debilitating in susceptible patients. Disease severity is controlled at specific innate immune checkpoints, and a detailed understanding of their functions is crucial for strategies to counter microbial aggression with novel treatment and prevention measures. One approach is the use of bacterial molecules that reprogramme the innate immune system, accelerating or inhibiting disease processes. A very different outcome is asymptomatic bacteriuria, defined by low host immune responsiveness to bacteria with attenuated virulence. This observation provides the rationale for immunomodulation as a new therapeutic tool to deliberately modify host susceptibility, control the host response and avoid severe disease. The power of innate immunity as an arbitrator of health and disease is also highly relevant for emerging pathogens, including the current COVID-19 pandemic.
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Affiliation(s)
- Ines Ambite
- grid.4514.40000 0001 0930 2361Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Daniel Butler
- grid.4514.40000 0001 0930 2361Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Murphy Lam Yim Wan
- grid.4514.40000 0001 0930 2361Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Therese Rosenblad
- grid.4514.40000 0001 0930 2361Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Thi Hien Tran
- grid.4514.40000 0001 0930 2361Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
| | - Sing Ming Chao
- Nephrology Service, Department of Paediatrics, KK Hospital, Singapore, Singapore
| | - Catharina Svanborg
- grid.4514.40000 0001 0930 2361Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
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12
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Girardet L, Bernet A, Calvo E, Soulet D, Joly-Beauparlant C, Droit A, Cyr DG, Belleannée C. Hedgehog signaling pathway regulates gene expression profile of epididymal principal cells through the primary cilium. FASEB J 2020; 34:7593-7609. [DOI: 10.1096/fj.202000328r] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/18/2020] [Accepted: 03/23/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Laura Girardet
- Faculty of Medicine Department of Obstetrics, Gynecology and Reproduction Université Laval, CHU de Québec Research Center (CHUL) Quebec City QC Canada
| | - Agathe Bernet
- Faculty of Medicine Department of Obstetrics, Gynecology and Reproduction Université Laval, CHU de Québec Research Center (CHUL) Quebec City QC Canada
| | - Ezéquiel Calvo
- Faculty of Medicine Department of Obstetrics, Gynecology and Reproduction Université Laval, CHU de Québec Research Center (CHUL) Quebec City QC Canada
| | - Denis Soulet
- Faculty of Pharmacy Université Laval, CHU de Québec Research Center (CHUL) Quebec City QC Canada
| | - Charles Joly-Beauparlant
- Computational Biology Laboratory Research Centre Faculty of Medicine Laval University Quebec City QC Canada
| | - Arnaud Droit
- Computational Biology Laboratory Research Centre Faculty of Medicine Laval University Quebec City QC Canada
| | - Daniel G. Cyr
- Faculty of Medicine Department of Obstetrics, Gynecology and Reproduction Université Laval, CHU de Québec Research Center (CHUL) Quebec City QC Canada
- Laboratory for Reproductive Toxicology INRS‐Institut Armand‐Frappier Université du Québec Laval QC Canada
| | - Clémence Belleannée
- Faculty of Medicine Department of Obstetrics, Gynecology and Reproduction Université Laval, CHU de Québec Research Center (CHUL) Quebec City QC Canada
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13
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Majumdar A, Trinh V, Moore KJ, Smallwood CR, Kumar A, Yang T, Scott DC, Long NJ, Newton SM, Klebba PE. Conformational rearrangements in the N-domain of Escherichia coli FepA during ferric enterobactin transport. J Biol Chem 2020; 295:4974-4984. [PMID: 32098871 DOI: 10.1074/jbc.ra119.011850] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 02/14/2020] [Indexed: 11/06/2022] Open
Abstract
The Escherichia coli outer membrane receptor FepA transports ferric enterobactin (FeEnt) by an energy- and TonB-dependent, but otherwise a mechanistically undetermined process involving its internal 150-residue N-terminal globular domain (N-domain). We genetically introduced pairs of Cys residues in different regions of the FepA tertiary structure, with the potential to form disulfide bonds. These included Cys pairs on adjacent β-strands of the N-domain (intra-N) and Cys pairs that bridged the external surface of the N-domain to the interior of the C-terminal transmembrane β-barrel (inter-N-C). We characterized FeEnt uptake by these mutants with siderophore nutrition tests, [59Fe]Ent binding and uptake experiments, and fluorescence decoy sensor assays. The three methods consistently showed that the intra-N disulfide bonds, which restrict conformational motion within the N-domain, prevented FeEnt uptake, whereas most inter-N-C disulfide bonds did not prevent FeEnt uptake. These outcomes indicate that conformational rearrangements must occur in the N terminus of FepA during FeEnt transport. They also argue against disengagement of the N-domain out of the channel as a rigid body and suggest instead that it remains within the transmembrane pore as FeEnt enters the periplasm.
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Affiliation(s)
- Aritri Majumdar
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Vy Trinh
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019
| | - Kyle J Moore
- Department of Chemistry, Physics and Engineering, Cameron University, Lawton, Oklahoma 73505
| | | | - Ashish Kumar
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Taihao Yang
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Daniel C Scott
- Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Noah J Long
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Salete M Newton
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
| | - Phillip E Klebba
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506
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14
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Pokorska J, Kułaj D, Ochrem A. Impact of bovine lipocalin-2 haplotype on milk composition, somatic cell score and incidence of mastitis in Polish Holstein-Friesian cattle. JOURNAL OF APPLIED ANIMAL RESEARCH 2020. [DOI: 10.1080/09712119.2020.1726354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Joanna Pokorska
- Department of Cattle Breeding, Institute of Animal Science, University of Agriculture in Krakow, Krakow, Poland
| | - Dominika Kułaj
- Department of Cattle Breeding, Institute of Animal Science, University of Agriculture in Krakow, Krakow, Poland
| | - Andrzej Ochrem
- Department of Cattle Breeding, Institute of Animal Science, University of Agriculture in Krakow, Krakow, Poland
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15
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Potts AH, Guo Y, Ahmer BMM, Romeo T. Role of CsrA in stress responses and metabolism important for Salmonella virulence revealed by integrated transcriptomics. PLoS One 2019; 14:e0211430. [PMID: 30682134 PMCID: PMC6347204 DOI: 10.1371/journal.pone.0211430] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 01/14/2019] [Indexed: 12/31/2022] Open
Abstract
To cause infection, Salmonella must survive and replicate in host niches that present dramatically different environmental conditions. This requires a flexible metabolism and physiology, responsive to conditions of the local milieu. The sequence specific RNA binding protein CsrA serves as a global regulator that governs gene expression required for pathogenicity, metabolism, biofilm formation, and motility in response to nutritional conditions. Its activity is determined by two noncoding small RNAs (sRNA), CsrB and CsrC, which sequester and antagonize this protein. Here, we used ribosome profiling and RNA-seq analysis to comprehensively examine the effects of CsrA on mRNA occupancy with ribosomes, a measure of translation, transcript stability, and the steady state levels of transcripts under in vitro SPI-1 inducing conditions, to simulate growth in the intestinal lumen, and under in vitro SPI-2-inducing conditions, to simulate growth in the Salmonella containing vacuole (SCV) of the macrophage. Our findings uncovered new roles for CsrA in controlling the expression of structural and regulatory genes involved in stress responses, metabolism, and virulence systems required for infection. We observed substantial variation in the CsrA regulon under the two growth conditions. In addition, CsrB/C sRNA levels were greatly reduced under the simulated intracellular conditions and were responsive to nutritional factors that distinguish the intracellular and luminal environments. Altogether, our results reveal CsrA to be a flexible regulator, which is inferred to be intimately involved in maintaining the distinct gene expression patterns associated with growth in the intestine and the macrophage.
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Affiliation(s)
- Anastasia H Potts
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States of America
| | - Yinping Guo
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States of America
| | - Brian M M Ahmer
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States of America
| | - Tony Romeo
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States of America
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16
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Chakravorty S, Shipelskiy Y, Kumar A, Majumdar A, Yang T, Nairn BL, Newton SM, Klebba PE. Universal fluorescent sensors of high-affinity iron transport, applied to ESKAPE pathogens. J Biol Chem 2019; 294:4682-4692. [PMID: 30679312 DOI: 10.1074/jbc.ra118.006921] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/18/2019] [Indexed: 11/06/2022] Open
Abstract
Sensitive assays of biochemical specificity, affinity, and capacity are valuable both for basic research and drug discovery. We created fluorescent sensors that monitor high-affinity binding reactions and used them to study iron acquisition by ESKAPE bacteria, which are frequently responsible for antibiotic-resistant infections. By introducing site-directed Cys residues in bacterial iron transporters and modifying them with maleimide fluorophores, we generated living cells or purified proteins that bind but do not transport target compounds. These constructs sensitively detected ligand concentrations in solution, enabling accurate, real-time spectroscopic analysis of membrane transport by other cells. We assessed the efficacy of these "fluorescent decoy" (FD) sensors by characterizing active iron transport in the ESKAPE bacteria. The FD sensors monitored uptake of both ferric siderophores and hemin by the pathogens. An FD sensor for a particular ligand was universally effective in observing the uptake of that compound by all organisms we tested. We adapted the FD sensors to microtiter format, where they allow high-throughput screens for chemicals that block iron uptake, without genetic manipulations of the virulent target organisms. Hence, screening assays with FD sensors facilitate studies of mechanistic biochemistry, as well as discovery of chemicals that inhibit prokaryotic membrane transport. With appropriate design, FD sensors are potentially applicable to any pro- or eukaryotic high-affinity ligand transport process.
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Affiliation(s)
- Somnath Chakravorty
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Yan Shipelskiy
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Ashish Kumar
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Aritri Majumdar
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Taihao Yang
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Brittany L Nairn
- the Department of Biological Sciences, Bethel University, St. Paul, Minnesota 55112
| | - Salete M Newton
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Phillip E Klebba
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
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17
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Jung M, Mertens C, Tomat E, Brüne B. Iron as a Central Player and Promising Target in Cancer Progression. Int J Mol Sci 2019; 20:ijms20020273. [PMID: 30641920 PMCID: PMC6359419 DOI: 10.3390/ijms20020273] [Citation(s) in RCA: 167] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 02/07/2023] Open
Abstract
Iron is an essential element for virtually all organisms. On the one hand, it facilitates cell proliferation and growth. On the other hand, iron may be detrimental due to its redox abilities, thereby contributing to free radical formation, which in turn may provoke oxidative stress and DNA damage. Iron also plays a crucial role in tumor progression and metastasis due to its major function in tumor cell survival and reprogramming of the tumor microenvironment. Therefore, pathways of iron acquisition, export, and storage are often perturbed in cancers, suggesting that targeting iron metabolic pathways might represent opportunities towards innovative approaches in cancer treatment. Recent evidence points to a crucial role of tumor-associated macrophages (TAMs) as a source of iron within the tumor microenvironment, implying that specifically targeting the TAM iron pool might add to the efficacy of tumor therapy. Here, we provide a brief summary of tumor cell iron metabolism and updated molecular mechanisms that regulate cellular and systemic iron homeostasis with regard to the development of cancer. Since iron adds to shaping major hallmarks of cancer, we emphasize innovative therapeutic strategies to address the iron pool of tumor cells or cells of the tumor microenvironment for the treatment of cancer.
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Affiliation(s)
- Michaela Jung
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
| | - Christina Mertens
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
| | - Elisa Tomat
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson, AZ 85721-0041, USA.
| | - Bernhard Brüne
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
- German Cancer Consortium (DKTK), Partner Site Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
- Project Group Translational Medicine and Pharmacology TMP, Fraunhofer Institute for Molecular Biology and Applied Ecology, 60596 Frankfurt, Germany.
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18
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Pfeifhofer-Obermair C, Tymoszuk P, Petzer V, Weiss G, Nairz M. Iron in the Tumor Microenvironment-Connecting the Dots. Front Oncol 2018; 8:549. [PMID: 30534534 PMCID: PMC6275298 DOI: 10.3389/fonc.2018.00549] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 11/06/2018] [Indexed: 12/18/2022] Open
Abstract
Iron metabolism and tumor biology are intimately linked. Iron facilitates the production of oxygen radicals, which may either result in iron-induced cell death, ferroptosis, or contribute to mutagenicity and malignant transformation. Once transformed, malignant cells require high amounts of iron for proliferation. In addition, iron has multiple regulatory effects on the immune system, thus affecting tumor surveillance by immune cells. For these reasons, inconsiderate iron supplementation in cancer patients has the potential of worsening disease course and outcome. On the other hand, chronic immune activation in the setting of malignancy alters systemic iron homeostasis and directs iron fluxes into myeloid cells. While this response aims at withdrawing iron from tumor cells, it may impair the effector functions of tumor-associated macrophages and will result in iron-restricted erythropoiesis and the development of anemia, subsequently. This review summarizes our current knowledge of the interconnections of iron homeostasis with cancer biology, discusses current clinical controversies in the treatment of anemia of cancer and focuses on the potential roles of iron in the solid tumor microenvironment, also speculating on yet unknown molecular mechanisms.
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Affiliation(s)
- Christa Pfeifhofer-Obermair
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Innsbruck, Austria
| | - Piotr Tymoszuk
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Innsbruck, Austria
| | - Verena Petzer
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Innsbruck, Austria
| | - Günter Weiss
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Innsbruck, Austria.,Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Innsbruck, Austria
| | - Manfred Nairz
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Innsbruck, Austria
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19
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Nairz M, Dichtl S, Schroll A, Haschka D, Tymoszuk P, Theurl I, Weiss G. Iron and innate antimicrobial immunity-Depriving the pathogen, defending the host. J Trace Elem Med Biol 2018; 48:118-133. [PMID: 29773170 DOI: 10.1016/j.jtemb.2018.03.007] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 02/25/2018] [Accepted: 03/06/2018] [Indexed: 02/08/2023]
Abstract
The acute-phase response is triggered by the presence of infectious agents and danger signals which indicate hazards for the integrity of the mammalian body. One central feature of this response is the sequestration of iron into storage compartments including macrophages. This limits the availability of this essential nutrient for circulating pathogens, a host defence strategy known as 'nutritional immunity'. Iron metabolism and the immune response are intimately linked. In infections, the availability of iron affects both the efficacy of antimicrobial immune pathways and pathogen proliferation. However, host strategies to withhold iron from microbes vary according to the localization of pathogens: Infections with extracellular bacteria such as Staphylococcus aureus, Streptococcus, Klebsiella or Yersinia stimulate the expression of the iron-regulatory hormone hepcidin which targets the cellular iron-exporter ferroportin-1 causing its internalization and blockade of iron egress from absorptive enterocytes in the duodenum and iron-recycling macrophages. This mechanism disrupts both routes of iron delivery to the circulation, contributes to iron sequestration in the mononuclear phagocyte system and mediates the hypoferraemia of the acute phase response subsequently resulting in the development of anaemia of inflammation. When intracellular microbes are present, other strategies of microbial iron withdrawal are needed. For instance, in macrophages harbouring intracellular pathogens such as Chlamydia, Mycobacterium tuberculosis, Listeria monocytogenes or Salmonella Typhimurium, ferroportin-1-mediated iron export is turned on for the removal of iron from infected cells. This also leads to reduced iron availability for intra-macrophage pathogens which inhibits their growth and in parallel strengthens anti-microbial effector pathways of macrophages including the formation of inducible nitric oxide synthase and tumour necrosis factor. Iron plays a key role in infectious diseases both as modulator of the innate immune response and as nutrient for microbes. We need to gain a more comprehensive understanding of how the body can differentially respond to infection by extra- or intracellular pathogens. This knowledge may allow us to modulate mammalian iron homeostasis pharmaceutically and to target iron-acquisition systems of pathogens, thus enabling us to treat infections with novel strategies that act independent of established antimicrobials.
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Affiliation(s)
- Manfred Nairz
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria.
| | - Stefanie Dichtl
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Andrea Schroll
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - David Haschka
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Piotr Tymoszuk
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Igor Theurl
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Günter Weiss
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
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20
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Martin RM, Bachman MA. Colonization, Infection, and the Accessory Genome of Klebsiella pneumoniae. Front Cell Infect Microbiol 2018; 8:4. [PMID: 29404282 PMCID: PMC5786545 DOI: 10.3389/fcimb.2018.00004] [Citation(s) in RCA: 452] [Impact Index Per Article: 75.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 01/05/2018] [Indexed: 12/22/2022] Open
Abstract
Klebsiella pneumoniae is a Gram-negative pathogen that has a large accessory genome of plasmids and chromosomal gene loci. This accessory genome divides K. pneumoniae strains into opportunistic, hypervirulent, and multidrug-resistant groups and separates K. pneumoniae from two closely related species, Klebsiella variicola and Klebsiella quasipneumoniae. Some strains of K. pneumoniae act as opportunistic pathogens, infecting critically ill and immunocompromised patients. These K. pneumoniae are a common cause of health-care associated infections including pneumonia, urinary tract infections (UTIs), and bloodstream infections. K. variicola and K. quasipneumoniae are often clinically indistinguishable from opportunistic K. pneumoniae. Other strains of K. pneumoniae are hypervirulent, infecting healthy people in community settings and causing severe infections including pyogenic liver abscess, endophthalmitis, and meningitis. A third group of K. pneumoniae encode carbapenemases, making them highly antibiotic-resistant. These strains act as opportunists but are exceedingly difficult to treat. All of these groups of K. pneumoniae and related species can colonize the gastrointestinal tract, and the accessory genome may determine if a colonizing strain remains asymptomatic or progresses to cause disease. This review will explore the associations between colonization and infection with opportunistic, antibiotic-resistant, and hypervirulent K. pneumoniae strains and the role of the accessory genome in distinguishing these groups and related species. As K. pneumoniae infections become progressively more difficult to treat in the face of antibiotic resistance and hypervirulent strains, an increased understanding of the epidemiology and pathogenesis of these bacteria is vital.
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Affiliation(s)
| | - Michael A. Bachman
- Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, MI, United States
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21
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Chanda W, Joseph TP, Padhiar AA, Guo X, Min L, Wang W, Lolokote S, Ning A, Cao J, Huang M, Zhong M. Combined effect of linolenic acid and tobramycin on Pseudomonas aeruginosa biofilm formation and quorum sensing. Exp Ther Med 2017; 14:4328-4338. [PMID: 29104645 PMCID: PMC5658730 DOI: 10.3892/etm.2017.5110] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 08/22/2017] [Indexed: 12/28/2022] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous Gram negative opportunistic pathogen capable of causing severe nosocomial infections in humans, and tobramycin is currently used to treat P. aeruginosa associated lung infections. Quorum sensing regulates biofilm formation which allows the bacterium to result in fatal infections forcing clinicians to extensively use antibiotics to manage its infections leading to emerging multiple drug resistant strains. As a result, tobramycin is also becoming resistant. Despite extensive studies on drug discovery to alleviate microbial drug resistance, the continued microbial evolution has forced researchers to focus on screening various phytochemicals and dietary compounds for antimicrobial potential. Linolenic acid (LNA) is an essential fatty acid that possesses antimicrobial actions on various microorganisms. It was hypothesized that LNA may affect the formation of biofilm on P. aeruginosa and improve the potency of tobramycin. The present study demonstrated that LNA interfered with cell-to-cell communication and reduced virulence factor production. It further enhanced the potency of tobramycin and synergistically inhibited biofilm formation through P. aeruginosa quorum sensing systems. Therefore, LNA may be considered as a potential agent for adjunctive therapy and its utilization may decrease tobramycin concentration in combined treatment thereby reducing aminoglycoside adverse effects.
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Affiliation(s)
- Warren Chanda
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Thomson Patrick Joseph
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Arshad Ahmed Padhiar
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Xuefang Guo
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Liu Min
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Wendong Wang
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Sainyugu Lolokote
- Department of Epidemiology and Biostatistics, School of Public Health, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Anhong Ning
- Laboratory of Pathogen Biology, Experimental Teaching Center for Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Jing Cao
- Laboratory of Pathogen Biology, Experimental Teaching Center for Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Min Huang
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
| | - Mintao Zhong
- Department of Microbiology, College of Basic Medical Sciences, Dalian Medical University, Dalian, Liaoning 116044 P.R. China
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Rocha ER, Krykunivsky AS. Anaerobic utilization of Fe(III)-xenosiderophores among Bacteroides species and the distinct assimilation of Fe(III)-ferrichrome by Bacteroides fragilis within the genus. Microbiologyopen 2017; 6:e00479. [PMID: 28397401 PMCID: PMC5552952 DOI: 10.1002/mbo3.479] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 02/24/2017] [Accepted: 03/07/2017] [Indexed: 01/01/2023] Open
Abstract
In this study, we show that Bacteroides species utilize Fe(III)-xenosiderophores as the only source of exogenous iron to support growth under iron-limiting conditions in vitro anaerobically. Bacteroides fragilis was the only species able to utilize Fe(III)-ferrichrome while Bacteroides vulgatus ATCC 8482 and Bacteroides thetaiotaomicron VPI 5482 were able to utilize both Fe(III)-enterobactin and Fe(III)-salmochelin S4 as the only source of iron in a dose-dependent manner. We have investigated the way B. fragilis assimilates Fe(III)-ferrichrome as initial model to understand the utilization of xenosiderophores in anaerobes. B. fragilis contains two outer membrane TonB-dependent transporters (TBDTs), FchA1 and FchA2, which are homologues to Escherichia coli ferrichrome transporter FhuA. The disruption of fchA1 gene had only partial growth defect on Fe(III)-ferrichrome while the fchA2 mutant had no growth defect compared to the parent strain. The genetic complementation of fchA1 gene restored growth to parent strain levels indicating that it plays a role in Fe(III)-ferrichrome assimilation though we cannot rule out some functional overlap in transport systems as B. fragilis contains abundant TBDTs whose functions are yet not understood. However, the growth of B. fragilis on Fe(III)-ferrichrome was abolished in a feoAB mutant indicating that Fe(III)-ferrichrome transported into the periplasmic space was reduced in the periplasm releasing ferrous iron prior to transport through the FeoAB transport system. Moreover, the release of iron from the ferrichrome may be linked to the thiol redox system as the trxB deletion mutant was also unable to grow in the presence of Fe(III)-ferrichrome. The genetic complementation of feoAB and trxB mutants completely restored growth on Fe(III)-ferrichrome. Taken together, these findings show that Bacteroides species have developed mechanisms to utilize ferric iron bound to xenosiderophores under anaerobic growth conditions though the regulation and role in the biology of Bacteroides in the anaerobic intestinal environment remain to be understood.
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Affiliation(s)
- Edson R. Rocha
- Department of Microbiology and ImmunologyBrody School of MedicineEast Carolina UniversityGreenvilleNC
| | - Anna S. Krykunivsky
- Department of Microbiology and ImmunologyBrody School of MedicineEast Carolina UniversityGreenvilleNC
- Intern from the Undergraduate Research Internship Placement ProgramUniversity of the West of England (UWE)BristolUK
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Nairz M, Theurl I, Swirski FK, Weiss G. "Pumping iron"-how macrophages handle iron at the systemic, microenvironmental, and cellular levels. Pflugers Arch 2017; 469:397-418. [PMID: 28251312 PMCID: PMC5362662 DOI: 10.1007/s00424-017-1944-8] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/25/2017] [Accepted: 01/29/2017] [Indexed: 12/12/2022]
Abstract
Macrophages reside in virtually every organ. First arising during embryogenesis, macrophages replenish themselves in the adult through a combination of self-renewal and influx of bone marrow-derived monocytes. As large phagocytic cells, macrophages participate in innate immunity while contributing to tissue-specific homeostatic functions. Among the key metabolic tasks are senescent red blood cell recycling, free heme detoxification, and provision of iron for de novo hemoglobin synthesis. While this systemic mechanism involves the shuttling of iron between spleen, liver, and bone marrow through the concerted function of defined macrophage populations, similar circuits appear to exist within the microenvironment of other organs. The high turnover of iron is the prerequisite for continuous erythropoiesis and tissue integrity but challenges macrophages’ ability to maintain cellular iron homeostasis and immune function. This review provides a brief overview of systemic, microenvironmental, and cellular aspects of macrophage iron handling with a focus on exciting and unresolved questions in the field.
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Affiliation(s)
- Manfred Nairz
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Anichstr. 35, 6020, Innsbruck, Austria. .,Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. .,Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Igor Theurl
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Anichstr. 35, 6020, Innsbruck, Austria
| | - Filip K Swirski
- Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.,Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Guenter Weiss
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Anichstr. 35, 6020, Innsbruck, Austria.
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Bearson BL. Molecular Profiling: Catecholamine Modulation of Gene Expression in Escherichia coli O157:H7 and Salmonella enterica Serovar Typhimurium. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 874:167-82. [DOI: 10.1007/978-3-319-20215-0_7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Zhang J, Gong F, Li L, Zhao M, Wu Z, Song J. The diagnostic value of neutrophil gelatinase-associated lipocalin and hepcidin in bacteria translocation of liver cirrhosis. Int J Clin Exp Med 2015; 8:16434-44. [PMID: 26629169 PMCID: PMC4659057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 09/10/2015] [Indexed: 06/05/2023]
Abstract
OBJECTIVE Bacterial translocation (BT) or bacterial DNA (bactDNA) translocation is a critical pathogenesis mechanism of spontaneous bacterial peritonitis. Studies of BT or bactDNA translocation are limited in humans. Neutrophil gelatinase associated lipocalin (NGAL) can efficiently distinguish bacterial and nonbacterial ascites in ascitic patients. Hepcidin is a useful marker of bacterial infection in the late-onset sepsis. However, the relationship between NGAL, hepcidin and BT was still unclear. In present study, the levels of NGAL, hepcidin and their relationship with BT or bactDNA translocation were investigated. MATERIAL AND METHODS Weekly doses of carbon tetrachloride (CCl4) were given to induce liver cirrhosis in Sprague-Dawley rats. Trypticase (blood) soy agars were used to culture bacteria. BactDNA was sequenced by ABIPRISM 310 automated sequencer. The levels of NGAL and hepcidin were assessed by ELISA. Receiver operating characteristic (ROC) curve was used to determine the cut-off values and compare the diagnostic performance of NGAL and hepcidin. RESULTS 56 cirrhotic and 10 normal rats were included in this study. The levels of both two biomarkers were significantly higher in BT or bactDNA translocation group compared to non-translocation group. The area under ROC curve for the diagnosis of BT was 0.910 for serum NGAL, 0.858 for serum hepcidin and 0.940 for their combination, whereas that for the diagnosis of bactDNA translocation was 0.906 for NGAL, 0.779 for hepcidin and 0.950 for their combination, respectively. The combination of NGAL and hepcidin improved the ability to detect BT or bactDNA presence in MLNs and ascites. CONCLUSION BT and the presence of bactDNA in MLNs were observed in a rat cirrhotic model. Serum NGAL and hepcidin can serve as sensitive and specific tests for diagnosis of BT or bactDNA translocation. NGAL in combination with hepcidin can improve the accuracy of diagnosis.
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Affiliation(s)
- Jiangguo Zhang
- Department of Infectious Diseases, Tongji Hospital, Huazhong University of Science and TechnologyWuhan 430030, Hubei, P. R. China
- Department of Gastroenterology, Shekou People’s HospitalShenzhen 518052, Guangdong, P. R. China
| | - Fengyun Gong
- Department of Infectious Diseases, The Fourth Hospital of WuhanWuhan 430030, Hubei, P. R. China
| | - Ling Li
- Department of Infectious Diseases, Tongji Hospital, Huazhong University of Science and TechnologyWuhan 430030, Hubei, P. R. China
| | - Manzhi Zhao
- Department of Infectious Diseases, Tongji Hospital, Huazhong University of Science and TechnologyWuhan 430030, Hubei, P. R. China
| | - Zhuhua Wu
- Department of Infectious Diseases, Tongji Hospital, Huazhong University of Science and TechnologyWuhan 430030, Hubei, P. R. China
| | - Jianxin Song
- Department of Infectious Diseases, Tongji Hospital, Huazhong University of Science and TechnologyWuhan 430030, Hubei, P. R. China
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Mycobacterium tuberculosis
infection of the ‘non‐classical immune cell’. Immunol Cell Biol 2015; 93:789-95. [DOI: 10.1038/icb.2015.43] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/02/2015] [Accepted: 03/18/2015] [Indexed: 01/29/2023]
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Nairz M, Schroll A, Demetz E, Tancevski I, Theurl I, Weiss G. 'Ride on the ferrous wheel'--the cycle of iron in macrophages in health and disease. Immunobiology 2014; 220:280-94. [PMID: 25240631 DOI: 10.1016/j.imbio.2014.09.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/20/2014] [Accepted: 09/05/2014] [Indexed: 12/16/2022]
Abstract
Iron homeostasis and macrophage biology are closely interconnected. On the one hand, iron exerts multiple effects on macrophage polarization and functionality. On the other hand, macrophages are central for mammalian iron homeostasis. The phagocytosis of senescent erythrocytes and their degradation by macrophages enable efficient recycling of iron and the maintenance of systemic iron balance. Macrophages express multiple molecules and proteins for the acquisition and utilization of iron and many of these pathways are affected by inflammatory signals. Of note, iron availability within macrophages has significant effects on immune effector functions and metabolic pathways within these cells. This review summarizes the physiological and pathophysiological aspects of macrophage iron metabolism and highlights its relevant consequences on immune function and in common diseases such as infection and atherosclerosis.
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Affiliation(s)
- Manfred Nairz
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria.
| | - Andrea Schroll
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Egon Demetz
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Ivan Tancevski
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Igor Theurl
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Günter Weiss
- Department of Internal Medicine VI, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria.
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Troxell B, Hassan HM. Transcriptional regulation by Ferric Uptake Regulator (Fur) in pathogenic bacteria. Front Cell Infect Microbiol 2013; 3:59. [PMID: 24106689 PMCID: PMC3788343 DOI: 10.3389/fcimb.2013.00059] [Citation(s) in RCA: 290] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/18/2013] [Indexed: 12/16/2022] Open
Abstract
In the ancient anaerobic environment, ferrous iron (Fe2+) was one of the first metal cofactors. Oxygenation of the ancient world challenged bacteria to acquire the insoluble ferric iron (Fe3+) and later to defend against reactive oxygen species (ROS) generated by the Fenton chemistry. To acquire Fe3+, bacteria produce low-molecular weight compounds, known as siderophores, which have extremely high affinity for Fe3+. However, during infection the host restricts iron from pathogens by producing iron- and siderophore-chelating proteins, by exporting iron from intracellular pathogen-containing compartments, and by limiting absorption of dietary iron. Ferric Uptake Regulator (Fur) is a transcription factor which utilizes Fe2+ as a corepressor and represses siderophore synthesis in pathogens. Fur, directly or indirectly, controls expression of enzymes that protect against ROS damage. Thus, the challenges of iron homeostasis and defense against ROS are addressed via Fur. Although the role of Fur as a repressor is well-documented, emerging evidence demonstrates that Fur can function as an activator. Fur activation can occur through three distinct mechanisms (1) indirectly via small RNAs, (2) binding at cis regulatory elements that enhance recruitment of the RNA polymerase holoenzyme (RNAP), and (3) functioning as an antirepressor by removing or blocking DNA binding of a repressor of transcription. In addition, Fur homologs control defense against peroxide stress (PerR) and control uptake of other metals such as zinc (Zur) and manganese (Mur) in pathogenic bacteria. Fur family members are important for virulence within bacterial pathogens since mutants of fur, perR, or zur exhibit reduced virulence within numerous animal and plant models of infection. This review focuses on the breadth of Fur regulation in pathogenic bacteria.
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Affiliation(s)
- Bryan Troxell
- Department of Immunology and Microbiology, Indiana University School of Medicine Indianapolis, IN, USA
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Multi-copper oxidases and human iron metabolism. Nutrients 2013; 5:2289-313. [PMID: 23807651 PMCID: PMC3738974 DOI: 10.3390/nu5072289] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/29/2013] [Accepted: 06/06/2013] [Indexed: 01/13/2023] Open
Abstract
Multi-copper oxidases (MCOs) are a small group of enzymes that oxidize their substrate with the concomitant reduction of dioxygen to two water molecules. Generally, multi-copper oxidases are promiscuous with regards to their reducing substrates and are capable of performing various functions in different species. To date, three multi-copper oxidases have been detected in humans—ceruloplasmin, hephaestin and zyklopen. Each of these enzymes has a high specificity towards iron with the resulting ferroxidase activity being associated with ferroportin, the only known iron exporter protein in humans. Ferroportin exports iron as Fe2+, but transferrin, the major iron transporter protein of blood, can bind only Fe3+ effectively. Iron oxidation in enterocytes is mediated mainly by hephaestin thus allowing dietary iron to enter the bloodstream. Zyklopen is involved in iron efflux from placental trophoblasts during iron transfer from mother to fetus. Release of iron from the liver relies on ferroportin and the ferroxidase activity of ceruloplasmin which is found in blood in a soluble form. Ceruloplasmin, hephaestin and zyklopen show distinctive expression patterns and have unique mechanisms for regulating their expression. These features of human multi-copper ferroxidases can serve as a basis for the precise control of iron efflux in different tissues. In this manuscript, we review the biochemical and biological properties of the three human MCOs and discuss their potential roles in human iron homeostasis.
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Behnsen J, Deriu E, Sassone-Corsi M, Raffatellu M. Probiotics: properties, examples, and specific applications. Cold Spring Harb Perspect Med 2013; 3:a010074. [PMID: 23457295 DOI: 10.1101/cshperspect.a010074] [Citation(s) in RCA: 152] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Probiotics are beneficial components of the microbiota that have been used for centuries because of the health benefits they confer to the host. Only recently, however, has the contribution of probiotics to modulation of immunological, respiratory, and gastrointestinal functions started to be fully appreciated and scientifically evaluated. Probiotics such as Escherichia coli Nissle 1917 and lactic acid bacteria are currently used to, or have been evaluated for use to, prevent or treat a range of intestinal maladies including inflammatory bowel disease, constipation, and colon cancer. Engineering these natural probiotics to produce immunomodulatory molecules may help to further increase the benefit to the host. In this article, we will discuss some of the mechanisms of action of probiotics as well as advances in the rational design of probiotics.
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Affiliation(s)
- Judith Behnsen
- Department of Microbiology and Molecular Genetics, Institute for Immunology, University of California, Irvine, CA 92697, USA
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Pyoverdine, the Major Siderophore in Pseudomonas aeruginosa, Evades NGAL Recognition. Interdiscip Perspect Infect Dis 2012; 2012:843509. [PMID: 22973307 PMCID: PMC3438788 DOI: 10.1155/2012/843509] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Accepted: 07/26/2012] [Indexed: 12/20/2022] Open
Abstract
Pseudomonas aeruginosa is the most common pathogen that persists in the cystic fibrosis lungs. Bacteria such as P. aeruginosa secrete siderophores (iron-chelating molecules) and the host limits bacterial growth by producing neutrophil-gelatinase-associated lipocalin (NGAL) that specifically scavenges bacterial siderophores, therefore preventing bacteria from establishing infection. P. aeruginosa produces a major siderophore known as pyoverdine, found to be important for bacterial virulence and biofilm development. We report that pyoverdine did not bind to NGAL, as measured by tryptophan fluorescence quenching, while enterobactin bound to NGAL effectively causing a strong response. The experimental data indicate that pyoverdine evades NGAL recognition. We then employed a molecular modeling approach to simulate the binding of pyoverdine to human NGAL using NGAL's published crystal structures. The docking of pyoverdine to NGAL predicted nine different docking positions; however, neither apo- nor ferric forms of pyoverdine docked into the ligand-binding site in the calyx of NGAL where siderophores are known to bind. The molecular modeling results offer structural support that pyoverdine does not bind to NGAL, confirming the results obtained in the tryptophan quenching assay. The data suggest that pyoverdine is a stealth siderophore that evades NGAL recognition allowing P. aeruginosa to establish chronic infections in CF lungs.
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Abstract
INTRODUCTION Since the first application of antibiotics to treat bacterial infections, the development and spread of resistance has been a persistent threat. An ever evolving pipeline of next-generation therapeutics is required for modern medicine to remain one step ahead of pathogens. AREAS COVERED This review describes recent efforts to develop drugs that interrupt the assimilation of iron by bacteria: a process that is vital to cellular homeostasis and is not currently targeted by antibiotics used in the clinic. This review also covers the mechanisms by which bacteria acquire iron for their environment, and details efforts to intervene in these processes, using small molecule inhibitors that target key steps in these pathways, with a special emphasis on recent advances published during the 2010 - 2012 period. EXPERT OPINION For decades, the routes used by bacteria to assimilate iron from host and environmental settings have been the subject of intense study. While numerous investigations have identified inhibitors of these pathways, many have stopped short of translating the in vitro results to in vivo proof of concept experiments. The extension of preliminary findings in this manner will significantly increase the impact of the field.
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Affiliation(s)
- Timothy L Foley
- National Institutes of Health, National Center for Advancing Translational Sciences, Division of Preclinical Innovation, 9800 Medical Center Drive, Bethesda, MD 20892-3370, USA
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Schmiederer T, Rausch S, Valdebenito M, Mantri Y, Mösker E, Baramov T, Stelmaszyk K, Schmieder P, Butz D, Müller SI, Schneider K, Baik MH, Hantke K, Süssmuth RD. Die E.-coli-Siderophore Enterobactin und Salmochelin bilden sechsfach koordinierte Siliciumkomplexe bei physiologischen pH-Werten. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201005792] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Schmiederer T, Rausch S, Valdebenito M, Mantri Y, Mösker E, Baramov T, Stelmaszyk K, Schmieder P, Butz D, Müller SI, Schneider K, Baik MH, Hantke K, Süssmuth RD. The E. coli Siderophores Enterobactin and Salmochelin Form Six-Coordinate Silicon Complexes at Physiological pH. Angew Chem Int Ed Engl 2011; 50:4230-3. [DOI: 10.1002/anie.201005792] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 11/30/2010] [Indexed: 11/11/2022]
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Abstract
The urinary tract is a common site of bacterial infections; nearly half of all women experience at least one urinary tract infection (UTI) during their lifetime. These infections are classified based on the condition of the host. Uncomplicated infections affect otherwise healthy individuals and are most commonly caused by uropathogenic Escherichia coli, whereas complicated infections affect patients with underlying difficulties, such as a urinary tract abnormality or catheterization, and are commonly caused by species such as Proteus mirabilis. Virulence and fitness factors produced by both pathogens include fimbriae, toxins, flagella, iron acquisition systems, and proteins that function in immune evasion. Additional factors that contribute to infection include the formation of intracellular bacterial communities by E. coli and the production of urease by P. mirabilis, which can result in urinary stone formation. Innate immune responses are induced or mediated by pattern recognition receptors, antimicrobial peptides, and neutrophils. The adaptive immune response to UTI is less well understood. Host factors TLR4 and CXCR1 are implicated in disease outcome and susceptibility, respectively. Low levels of TLR4 are associated with asymptomatic bacteriuria while low levels of CXCR1 are associated with increased incidence of acute pyelonephritis. Current research is focused on the identification of additional virulence factors and therapeutic or prophylactic targets that might be used in the generation of vaccines against both uropathogens.
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Sivick KE, Mobley HLT. Waging war against uropathogenic Escherichia coli: winning back the urinary tract. Infect Immun 2010; 78:568-85. [PMID: 19917708 PMCID: PMC2812207 DOI: 10.1128/iai.01000-09] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Urinary tract infection (UTI) caused by uropathogenic Escherichia coli (UPEC) is a substantial economic and societal burden-a formidable public health issue. Symptomatic UTI causes significant discomfort in infected patients, results in lost productivity, predisposes individuals to more serious infections, and usually necessitates antibiotic therapy. There is no licensed vaccine available for prevention of UTI in humans in the United States, likely due to the challenge of targeting a relatively heterogeneous group of pathogenic strains in a unique physiological niche. Despite significant advances in the understanding of UPEC biology, mechanistic details regarding the host response to UTI and full comprehension of genetic loci that influence susceptibility require additional work. Currently, there is an appreciation for the role of classic innate immune responses-from pattern receptor recognition to recruitment of phagocytic cells-that occur during UPEC-mediated UTI. There is, however, a clear disconnect regarding how factors involved in the innate immune response to UPEC stimulate acquired immunity that facilitates enhanced clearance upon reinfection. Unraveling the molecular details of this process is vital in the development of a successful vaccine for prevention of human UTI. Here, we survey the current understanding of host responses to UPEC-mediated UTI with an eye on molecular and cellular factors whose activity may be harnessed by a vaccine that stimulates lasting and sterilizing immunity.
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Affiliation(s)
- Kelsey E. Sivick
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Harry L. T. Mobley
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109
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Stopková R, Zdráhal Z, Ryba S, Sedo O, Sandera M, Stopka P. Novel OBP genes similar to hamster Aphrodisin in the bank vole, Myodes glareolus. BMC Genomics 2010; 11:45. [PMID: 20085627 PMCID: PMC2824723 DOI: 10.1186/1471-2164-11-45] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 01/19/2010] [Indexed: 12/03/2022] Open
Abstract
Background Chemical communication in mammals involves globular lipocalins that protect and transport pheromones during their passage out of the body. Efficient communication via this protein - pheromone complex is essential for triggering multiple responses including aggression, mate choice, copulatory behaviour, and onset and synchronization of oestrus. The roles of lipocalins in communication were studied in many organisms and especially in mice (i.e. Mus musculus domesticus) which excrete Major Urinary Proteins (Mup) in excessive amounts in saliva and urine. Other mammals, however, often lack the genes for Mups or their expression is very low. Therefore, we aimed at characterization of candidate lipocalins in Myodes glareolus which are potentially linked to chemical communication. One of them is Aphrodisin which is a unique lipocalin that was previously described from hamster vaginal discharge and is known to carry pheromones stimulating copulatory behaviour in males. Results Here we show that Aphrodisin-like proteins exist in other species, belong to a group of Odorant Binding Proteins (Obp), and contrary to the expression of Aphrodisin only in hamster genital tract and parotid glands of females, we have detected these transcripts in both sexes of M. glareolus with the expression confirmed in various tissues including prostate, prepucial and salivary glands, liver and uterus. On the level of mRNA, we have detected three different gene variants. To assess their relevance for chemical communication we investigated the occurrence of particular proteins in saliva, urine and vaginal discharge. On the protein level we confirmed the presence of Obp2 and Obp3 in both saliva and urine. Appropriate bands in the range of 17-20 kDa from vaginal discharge were, however, beyond the MS detection limits. Conclusion Our results demonstrate that three novel Obps (Obp1, Obp2, and Obp3) are predominant lipocalins in Myodes urine and saliva. On the protein level we have detected further variants and thus we assume that similarly as Major Urinary Proteins in mice, these proteins may be important in chemical communication in this Cricetid rodent.
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Affiliation(s)
- Romana Stopková
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, CZ-128 44, Czech Republic
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Azpiroz MF, Poey ME, Laviña M. Microcins and urovirulence in Escherichia coli. Microb Pathog 2009; 47:274-80. [DOI: 10.1016/j.micpath.2009.09.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 08/27/2009] [Accepted: 09/01/2009] [Indexed: 11/16/2022]
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Saiga H, Nishimura J, Kuwata H, Okuyama M, Matsumoto S, Sato S, Matsumoto M, Akira S, Yoshikai Y, Honda K, Yamamoto M, Takeda K. Lipocalin 2-dependent inhibition of mycobacterial growth in alveolar epithelium. THE JOURNAL OF IMMUNOLOGY 2009; 181:8521-7. [PMID: 19050270 DOI: 10.4049/jimmunol.181.12.8521] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mycobacterium tuberculosis invades alveolar epithelial cells as well as macrophages. However, the role of alveolar epithelial cells in the host defense against M. tuberculosis remains unknown. In this study, we report that lipocalin 2 (Lcn2)-dependent inhibition of mycobacterial growth within epithelial cells is required for anti-mycobacterial innate immune responses. Lcn2 is secreted into the alveolar space by alveolar macrophages and epithelial cells during the early phase of respiratory mycobacterial infection. Lcn2 inhibits the in vitro growth of mycobacteria through sequestration of iron uptake. Lcn2-deficient mice are highly susceptible to intratracheal infection with M. tuberculosis. Histological analyses at the early phase of mycobacterial infection in Lcn2-deficient mice reveal increased numbers of mycobacteria in epithelial cell layers, but not in macrophages, in the lungs. Increased intracellular mycobacterial growth is observed in alveolar epithelial cells, but not in alveolar macrophages, from Lcn2-deficient mice. The inhibitory action of Lcn2 is blocked by the addition of endocytosis inhibitors, suggesting that internalization of Lcn2 into the epithelial cells is a prerequisite for the inhibition of intracellular mycobacterial growth. Taken together, these findings highlight a pivotal role for alveolar epithelial cells during mycobacterial infection, in which Lcn2 mediates anti-mycobacterial innate immune responses within the epithelial cells.
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Affiliation(s)
- Hiroyuki Saiga
- Department of Microbiology and Immunology, Laboratory of Immune Regulation, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
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Iron regulated genes of Salmonella enterica serovar Typhimurium in response to norepinephrine and the requirement of fepDGC for norepinephrine-enhanced growth. Microbes Infect 2008; 10:807-16. [DOI: 10.1016/j.micinf.2008.04.011] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 03/14/2008] [Accepted: 04/16/2008] [Indexed: 11/22/2022]
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Adiposity in women and children from transition countries predicts decreased iron absorption, iron deficiency and a reduced response to iron fortification. Int J Obes (Lond) 2008; 32:1098-104. [PMID: 18427564 DOI: 10.1038/ijo.2008.43] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Overweight is increasing in transition countries, while iron deficiency remains common. In industrialized countries, greater adiposity increases risk of iron deficiency. Higher hepcidin levels in obesity may reduce dietary iron absorption. Therefore, we investigated the association between body mass index (BMI) and iron absorption, iron status and the response to iron fortification in populations from three transition countries (Thailand, Morocco and India). METHODS In Thai women (n=92), we examined the relationship between BMI and iron absorption from a reference meal containing approximately 4 mg of isotopically labeled fortification iron. We analyzed data from baseline (n=1688) and intervention (n=727) studies in children in Morocco and India to look for associations between BMI Z-scores and baseline hemoglobin, serum ferritin and transferrin receptor, whole blood zinc protoporphyrin and body iron stores, and changes in these measures after provision of iron. RESULTS In the Thai women, 20% were iron deficient and 22% were overweight. Independent of iron status, a higher BMI Z-score was associated with decreased iron absorption (P=0.030). In the Indian and Moroccan children, 42% were iron deficient and 6.3% were overweight. A higher BMI Z-score predicted poorer iron status at baseline (P<0.001) and less improvement in iron status during the interventions (P<0.001). CONCLUSIONS Adiposity in young women predicts lower iron absorption, and pediatric adiposity predicts iron deficiency and a reduced response to iron fortification. These data suggest the current surge in overweight in transition countries may impair efforts to control iron deficiency in these target groups. Interactions of the 'double burden' of malnutrition during the nutrition transition may have adverse consequences.
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Origins and virulence mechanisms of uropathogenic Escherichia coli. Exp Mol Pathol 2008; 85:11-9. [PMID: 18482721 DOI: 10.1016/j.yexmp.2008.03.007] [Citation(s) in RCA: 377] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Accepted: 03/02/2008] [Indexed: 11/23/2022]
Abstract
Strains of uropathogenic E. coli (UPEC) are the primary cause of urinary tract infections, including both cystitis and pyelonephritis. These bacteria have evolved a multitude of virulence factors and strategies that facilitate bacterial growth and persistence within the adverse settings of the host urinary tract. Expression of adhesive organelles like type 1 and P pili allow UPEC to bind and invade host cells and tissues within the urinary tract while expression of iron-chelating factors (siderophores) enable UPEC to pilfer host iron stores. Deployment of an array of toxins, including hemolysin and cytotoxic necrotizing factor 1, provide UPEC with the means to inflict extensive tissue damage, facilitating bacterial dissemination as well as releasing host nutrients and disabling immune effector cells. These toxins also have the capacity to modulate, in more subtle ways, host signaling pathways affecting myriad processes, including inflammatory responses, host cell survival, and cytoskeletal dynamics. Here, we discuss the mechanisms by which these and other virulence factors promote UPEC survival and growth within the urinary tract. Comparisons are also made between UPEC and other strains of extraintestinal pathogenic E. coli that, although closely related to UPEC, are distinct in their abilities to colonize the host and cause disease.
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