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Zeng P, Wang H, Zhang P, Leung SSY. Unearthing naturally-occurring cyclic antibacterial peptides and their structural optimization strategies. Biotechnol Adv 2024; 73:108371. [PMID: 38704105 DOI: 10.1016/j.biotechadv.2024.108371] [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: 11/10/2023] [Revised: 03/08/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024]
Abstract
Natural products with antibacterial activity are highly desired globally to combat against multidrug-resistant (MDR) bacteria. Antibacterial peptide (ABP), especially cyclic ABP (CABP), is one of the abundant classes. Most of them were isolated from microbes, demonstrating excellent bactericidal effects. With the improved proteolytic stability, CABPs are normally considered to have better druggability than linear peptides. However, most clinically-used CABP-based antibiotics, such as colistin, also face the challenges of drug resistance soon after they reached the market, urgently requiring the development of next-generation succedaneums. We present here a detail review on the novel naturally-occurring CABPs discovered in the past decade and some of them are under clinical trials, exhibiting anticipated application potential. According to their chemical structures, they were broadly classified into five groups, including (i) lactam/lactone-based CABPs, (ii) cyclic lipopeptides, (iii) glycopeptides, (iv) cyclic sulfur-rich peptides and (v) multiple-modified CABPs. Their chemical structures, antibacterial spectrums and proposed mechanisms are discussed. Moreover, engineered analogs of these novel CABPs are also summarized to preliminarily analyze their structure-activity relationship. This review aims to provide a global perspective on research and development of novel CABPs to highlight the effectiveness of derivatives design in identifying promising antibacterial agents. Further research efforts in this area are believed to play important roles in fighting against the multidrug-resistance crisis.
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Affiliation(s)
- Ping Zeng
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Honglan Wang
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Pengfei Zhang
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Sharon Shui Yee Leung
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
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2
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Kumar G, Engle K. Natural products acting against S. aureus through membrane and cell wall disruption. Nat Prod Rep 2023; 40:1608-1646. [PMID: 37326041 DOI: 10.1039/d2np00084a] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Covering: 2015 to 2022Staphylococcus aureus (S. aureus) is responsible for several community and hospital-acquired infections with life-threatening complications such as bacteraemia, endocarditis, meningitis, liver abscess, and spinal cord epidural abscess. In recent decades, the abuse and misuse of antibiotics in humans, animals, plants, and fungi and the treatment of nonmicrobial diseases have led to the rapid emergence of multidrug-resistant pathogens. The bacterial wall is a complex structure consisting of the cell membrane, peptidoglycan cell wall, and various associated polymers. The enzymes involved in bacterial cell wall synthesis are established antibiotic targets and continue to be a central focus for antibiotic development. Natural products play a vital role in drug discovery and development. Importantly, natural products provide a starting point for active/lead compounds that sometimes need modification based on structural and biological properties to meet the drug criteria. Notably, microorganisms and plant metabolites have contributed as antibiotics for noninfectious diseases. In this study, we have summarized the recent advances in understanding the activity of the drugs or agents of natural origin that directly inhibit the bacterial membrane, membrane components, and membrane biosynthetic enzymes by targeting membrane-embedded proteins. We also discussed the unique aspects of the active mechanisms of established antibiotics or new agents.
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Affiliation(s)
- Gautam Kumar
- Department of Natural Products, Chemical Sciences, National Institute of Pharmaceutical Education and Research-Hyderabad, Hyderabad, Balanagar, 500037, India.
| | - Kritika Engle
- Department of Natural Products, Chemical Sciences, National Institute of Pharmaceutical Education and Research-Hyderabad, Hyderabad, Balanagar, 500037, India.
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Fu J, Nakata Y, Itoh H, Panthee S, Hamamoto H, Sekimizu K, Inoue M. Molecular Editing Enhances Oxidation Resistance of Menaquinone-Targeting Antibiotics Lysocin E and WAP-8294A2. Chemistry 2023; 29:e202301224. [PMID: 37328428 DOI: 10.1002/chem.202301224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/16/2023] [Accepted: 06/16/2023] [Indexed: 06/18/2023]
Abstract
Lysocin E (1 a) and WAP-8294A2 (2 a) are peptidic natural products with 37- and 40-membered macrocycles, respectively. Compounds 1 a and 2 a have potent antibacterial activities against Gram-positive bacteria and share a unique mode of action. The electron-rich indole ring of d-Trp-10 of 1 a and 2 a interacts with the electron-deficient benzoquinone ring of menaquinone, which is a co-enzyme in the bacterial respiratory chain. Formation of the electron-donor-acceptor complex causes membrane disruption, leading to cell death. Despite the promising activities of 1 a and 2 a, the susceptibility of Trp-10 to oxidative degradation potentially deters the development of these compounds as antibacterial drugs. To address this issue, we replaced the indole ring with more oxidation-resistant aromatics having a similar shape and electron-rich character. Specifically, analogues with benzofuran (1 b/2 b), benzothiophene (1 c/2 c), and 1-naphthalene (1 d/2 d) rings were designed, and chemically prepared by full solid-phase total syntheses. Antibacterial assays of the six analogues revealed similar activities of 1 d/2 d and markedly reduced activities of 1 b/2 b and 1 c/2 c compared with 1 a/2 a. Equipotent 1 d and 2 d both showed high resistance to oxidation by peroxyl radicals. Hence, the present study demonstrates a new molecular editing strategy for conferring oxidation stability on natural products with pharmacologically useful functions.
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Affiliation(s)
- Junhao Fu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yosuke Nakata
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Hiroaki Itoh
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Suresh Panthee
- GenEndeavor LLC, 26219 Eden Landing Rd, Hayward, CA, 94545, USA
- Faculty of Pharma-Science, Teikyo University, 359 Otsuka, Hachioji, Tokyo, 192-0395, Japan
| | - Hiroshi Hamamoto
- Yamagata University Faculty of Medicine, 2-2-2 Iida-Nishi, Yamagata, Yamagata, 990-9585, Japan
| | - Kazuhisa Sekimizu
- Faculty of Pharma-Science, Teikyo University, 359 Otsuka, Hachioji, Tokyo, 192-0395, Japan
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
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Huang Y, Feng J, Li Q, Zhang Z, Jiang B, Amoah K, Huang Y, Jian J. Apolipoprotein A-I (ApoA-I) protects Nile tilapia (Oreochromis niloticus) against bacterial infection. FISH & SHELLFISH IMMUNOLOGY 2023:108925. [PMID: 37414306 DOI: 10.1016/j.fsi.2023.108925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 06/20/2023] [Accepted: 07/02/2023] [Indexed: 07/08/2023]
Abstract
Apolipoprotein A-I (ApoA-I) is a lipoprotein involved in a variety of physiological and pathological processes. However, the immunomodulatory functions of ApoA-I in fish are not well understood. In this study, ApoA-I from Nile tilapia (Oreochromis niloticus) (On-ApoA-I) was identified, and its function in bacterial infection was investigated. The open reading frame of On-ApoA-I is 792 bp, which codes for a protein containing 263 amino acids. On-ApoA-I shared over 60% sequence similarity with other teleost fish and more than 20% with mammalian ApoA-I. On-ApoA-I was found to be highly expressed in the liver and significantly induced during Streptococcus agalactiae infection by qRT‒PCR analysis. Furthermore, in vivo studies revealed that recombinant On-ApoA-I protein could suppress inflammation and apoptosis and improve the likelihood of surviving bacterial infection. Additionally, On-ApoA-I showed in vitro antimicrobial properties against Gram-positive and Gram-negative bacteria. These findings offer a theoretical basis for further investigations into the role of ApoA-I in fish immunology.
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Affiliation(s)
- Yongxiong Huang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China
| | - Jiamin Feng
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China
| | - Qi Li
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China
| | - Zhiqiang Zhang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China
| | - Baijian Jiang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China
| | - Kwaku Amoah
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China
| | - Yu Huang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China; Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen, China.
| | - Jichang Jian
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture & Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institutes, Zhanjiang, 524088, China; Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen, China.
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Hamamoto H, Miyashita A, Kamura K, Horie R, Sekimizu K. Silkworm arylsulfatase in the midgut content is expressed in the silk gland and fed via smearing on the food from the spinneret. Drug Discov Ther 2022; 16:280-285. [PMID: 36450504 DOI: 10.5582/ddt.2022.01088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
We found the activity of arylsulfatase in the midgut contents of the silkworm, Bombyx mori. We identified a 60-kDa protein that comigrates with the activity on a column chromatography following ammonium sulfate precipitation. Based on its partial amino acid sequence, we searched for its coding gene using Basic Local Alignment Search Tool (BLAST) and identified KWMTBOMO05106. Transcriptional data suggest a specific expression of the gene in middle silk glands. The majority (80%) of arylsulfatase activity was found in the silk glands, concurring the specific transcription in the silk gland. Observing the feeding behaviour of the silkworm, we found that silkworms smear a mucus secretes from the spinneret on the food pellet as they feed on. Arylsulfatase activity was also detected in the food pellet bitten by the silkworm as well as in the gut content. Furthermore, arylsulfatase activity was not detected either in the food pellet and in the gut content when silkworms had obstructed the spinneret. These results suggest that arylsulfatase is secreted from the silk glands and may contribute to digestive function.
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Affiliation(s)
| | | | - Koushirou Kamura
- Drug Discoveries by Silkworm Models, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
| | - Ryo Horie
- Drug Discoveries by Silkworm Models, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
| | - Kazuhisa Sekimizu
- Drug Discoveries by Silkworm Models, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
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Lysocin E Targeting Menaquinone in the Membrane of Mycobacterium tuberculosis Is a Promising Lead Compound for Antituberculosis Drugs. Antimicrob Agents Chemother 2022; 66:e0017122. [PMID: 35969044 PMCID: PMC9487456 DOI: 10.1128/aac.00171-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tuberculosis remains a public health crisis and a health security threat. There is an urgent need to develop new antituberculosis drugs with novel modes of action to cure drug-resistant tuberculosis and shorten the chemotherapy period by sterilizing tissues infected with dormant bacteria. Lysocin E is an antibiotic that showed antibacterial activity against Staphylococcus aureus by binding to its menaquinone (commonly known as vitamin K2). Unlike S. aureus, menaquinone is essential in both growing and dormant Mycobacterium tuberculosis. This study aims to evaluate the antituberculosis activities of lysocin E and decipher its mode of action. We show that lysocin E has high in vitro activity against both drug-susceptible and drug-resistant Mycobacterium tuberculosis var. tuberculosis and dormant mycobacteria. Lysocin E is likely bound to menaquinone, causing M. tuberculosis membrane disruption, inhibition of oxygen consumption, and ATP synthesis. Thus, we have concluded that the high antituberculosis activity of lysocin E is attributable to its synergistic effects of membrane disruption and respiratory inhibition. The efficacy of lysocin E against intracellular M. tuberculosis in macrophages was lower than its potent activity against M. tuberculosis in culture medium, probably due to its low ability to penetrate cells, but its efficacy in mice was still superior to that of streptomycin. Our findings indicate that lysocin E is a promising lead compound for the development of a new tuberculosis drug that cures drug-resistant and latent tuberculosis in a shorter period.
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Wang X, Hong X, Chen F, Wang KJ. A truncated peptide Spgillcin177–189 derived from mud crab Scylla paramamosain exerting multiple antibacterial activities. Front Cell Infect Microbiol 2022; 12:928220. [PMID: 36061863 PMCID: PMC9435603 DOI: 10.3389/fcimb.2022.928220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/01/2022] [Indexed: 11/13/2022] Open
Abstract
Antimicrobial peptides (AMPs) may be the most promising substitute for antibiotics due to their effective bactericidal activity and multiple antimicrobial modes against pathogenic bacteria. In this study, a new functional gene named Spgillcin was identified in Scylla paramamosain, which encoded 216 amino acids of mature peptide. In vivo, Spgillcin was dominantly expressed in the gills of male and female crabs, offering the highest expression level among all tested organs or tissues. The expression pattern of Spgillcin was significantly altered when challenged by Staphylococcus aureus, indicating a positive immune response. In vitro, a functional truncated peptide Spgillcin177–189 derived from the amino acid sequence of Spgillcin was synthesized and showed a broad-spectrum and potent antibacterial activity against several bacterial strains, including the clinical isolates of multidrug-resistant (MDR) strains, with a range of minimum inhibitory concentrations from 1.5 to 48 μM. Spgillcin177–189 also showed rapid bactericidal kinetics for S. aureus and Pseudomonas aeruginosa but did not display any cytotoxicity to mammalian cells and maintained its antimicrobial activity in different conditions. Mechanistic studies indicated that Spgillcin177–189 was mainly involved in the disruption of cell membrane integrity where the membrane components lipoteichoic acid and lipopolysaccharide could significantly inhibit the antimicrobial activity in a dose-dependent manner. In addition, Spgillcin177–189 could change the membrane permeability and cause the accumulation of intracellular reactive oxygen species. No resistance was generated to Spgillcin177–189 when the clinical isolates of methicillin-resistant S. aureus and MDR P. aeruginosa were treated with Spgillcin177–189 and then subjected to a long term of continuous culturing for 50 days. In addition, Spgillcin177–189 exerted a strong anti-biofilm activity by inhibiting biofilm formation and was also effective at killing extracellular S. aureus in the cultural supernatant of RAW 264.7 cells. Taken together, Spgillcin177–189 has strong potential as a substitute for antibiotics in future aquaculture and medical applications.
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Affiliation(s)
- Xiaofei Wang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Xiao Hong
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Fangyi Chen
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- State-Province Joint Engineering Laboratory of Marine Bioproducts and Technology, College of Ocean and Earth Sciences, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Fujian Innovation Research Institute for Marine Biological Antimicrobial Peptide Industrial Technology, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Ke-Jian Wang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- State-Province Joint Engineering Laboratory of Marine Bioproducts and Technology, College of Ocean and Earth Sciences, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Fujian Innovation Research Institute for Marine Biological Antimicrobial Peptide Industrial Technology, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- *Correspondence: Ke-Jian Wang,
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Wang Q, Sun Z, Ma S, Liu X, Xia H, Chen K. Molecular mechanism and potential application of bacterial infection in the silkworm, Bombyx mori. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 131:104381. [PMID: 35245606 DOI: 10.1016/j.dci.2022.104381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/14/2022] [Accepted: 02/27/2022] [Indexed: 06/14/2023]
Abstract
As a representative species of Lepidoptera, Bombyx mori has been widely studied and applied. However, bacterial infection has always been an important pathogen threatening the growth of silkworms. Bombyx mori can resist various pathogenic bacteria through their own physical barrier and innate immune system. However, compared with other insects, such as Drosophila melanogaster, research on the antibacterial mechanism of silkworms is still in its infancy. This review systematically summarized the routes of bacterial infection in silkworms, the antibacterial mechanism of silkworms after ingestion or wounding infection, and the intestinal bacteria and infection of silkworms. Finally, we will discuss silkworms as a model animal for studying bacterial infectious diseases and screening antibacterial drugs.
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Affiliation(s)
- Qiang Wang
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Zhonghe Sun
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Shangshang Ma
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Xiaoyong Liu
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Hengchuan Xia
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Keping Chen
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, PR China.
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Peanut triacylglycerols activate innate immunity both in insects and mammals. Sci Rep 2022; 12:7464. [PMID: 35523841 PMCID: PMC9076670 DOI: 10.1038/s41598-022-11494-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 04/12/2022] [Indexed: 11/08/2022] Open
Abstract
In this study, we investigated immunoreactivity of peanut (Arachis hypogaea) oil using the silkworm (Bombyx mori) model. The peanut oil induced melanin formation when injected to the silkworm hemocoel. We then purified the active substance and identified the triacylglycerols (TAGs) as the responsible molecule for the melanin-forming effect of peanut oil. Also, the peanut TAGs induced the muscle contraction of the silkworm (i.e., cleavage of the insect cytokine BmPP) and the TNF-α production by cultured mouse macrophage cells. The muscle contraction activity of the peanut TAGs was reduced by saponification reaction, indicating that the TAG (not the degraded fatty acids) moiety is responsible for the activity. The muscle contraction effects of other TAGs of olive, lard, and beef oil were comparable with that of peanut TAGs. Nevertheless, for the melanin formation, the effect of peanut TAGs was outstanding. The fatty acid composition of peanut TAGs was distinct from that of olive TAGs. These results suggest that TAGs are immunoreactive and induces cytokines both in insect and mammalian immune systems. Also, the differential effects of peanut and olive TAGs for the melanin formation may suggest that TAGs with different fatty acid compositions are distinguished by the immune system.
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Miyashita A, Mitsutomi S, Mizushima T, Sekimizu K. Repurposing the PDMA-approved drugs in Japan using an insect model of staphylococcal infection. FEMS MICROBES 2022. [DOI: 10.1093/femsmc/xtac014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
A thousand and two hundred fifty-three (1253) compounds approved as therapeutic drugs in Japan (PMDA-approved compounds) were screened for their therapeutic effects against Staphylococcus aureus infection using the silkworm infection model. In the first stage of screening with an index of prolonged survival, 80 compounds were identified as hits. Of these, 64 compounds were clinically used as antimicrobial agents, and the remaining 16 compounds were not. The 16 compounds were examined for their dose-dependent therapeutic effects on the silkworm model as a second screening step, and we obtained five compounds as a result. One of the compounds (capecitabine) had no documented in vitro minimum inhibitory concentration (MIC) value against S. aureus. The MIC value of capecitabine against S. aureus strains ranged from 125 to 250 µg/mL Capecitabine was therapeutically effective at a dose of 200 mg/kg in a murine model of S. aureus infection. These results suggest that silkworm-based drug repositioning studies are of potential value. Furthermore, the therapeutic effects of capecitabine demonstrated in this study provide an important scientific rationale for clinical observational studies examining the association between staphylococcal infection events and capecitabine administration in cancer chemotherapy patients.
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Affiliation(s)
| | | | | | - Kazuhisa Sekimizu
- School of Pharma-Science, Teikyo University, Tokyo, Japan
- Genome Pharmaceuticals Institute, Co., Ltd., Tokyo, Japan
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