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Salazar-Villatoro L, Chávez-Munguía B, Guevara-Estrada CE, Lagunes-Guillén A, Hernández-Martínez D, Castelan-Ramírez I, Omaña-Molina M. Taurine, a Component of the Tear Film, Exacerbates the Pathogenic Mechanisms of Acanthamoeba castellanii in the Ex Vivo Amoebic Keratitis Model. Pathogens 2023; 12:1049. [PMID: 37624009 PMCID: PMC10458499 DOI: 10.3390/pathogens12081049] [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: 07/29/2023] [Revised: 08/13/2023] [Accepted: 08/14/2023] [Indexed: 08/26/2023] Open
Abstract
Acanthamoeba spp. is the etiological agent of amoebic keratitis. In this study, the effect of taurine in physiological concentrations in tears (195 μM) on trophozoites of Acanthamoeba castellanii through the ex vivo amoebic keratitis model was evaluated. Trophozoites were coincubated with the Syrian golden hamster cornea (Mesocricetus auratus) for 3 and 6 h. Group 1: Control (-). Corneas coincubated with amoebic culture medium and taurine. Group 2: Control (+). Corneas coincubated with trophozoites without taurine. Group 3: Corneas coincubated with taurine 15 min before adding trophozoites. Group 4: Trophozoites coincubated 15 min with taurine before placing them on the cornea. Group 5: Corneas coincubated for 15 min with trophozoites; subsequently, taurine was added. Results are similar for both times, as evaluated by scanning electron microscopy. As expected, in the corneas of Group 1, no alterations were observed in the corneal epithelium. In the corneas of Group 2, few adhered trophozoites were observed on the corneal surface initiating migrations through cell junctions as previously described; however, in corneas of Groups 3, 4 and 5, abundant trophozoites were observed, penetrating through different corneal cell areas, emitting food cups and destabilizing corneal surface in areas far from cell junctions. Significant differences were confirmed in trophozoites adherence coincubated with taurine (p < 0.05). Taurine does not prevent the adhesion and invasion of the amoebae, nor does it favor its detachment once these have adhered to the cornea, suggesting that taurine in the physiological concentrations found in tears stimulates pathogenic mechanisms of A. castellanii.
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Affiliation(s)
- Lizbeth Salazar-Villatoro
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de Mexico 07360, Mexico; (L.S.-V.); (B.C.-M.); (A.L.-G.)
| | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de Mexico 07360, Mexico; (L.S.-V.); (B.C.-M.); (A.L.-G.)
| | - Celia Esther Guevara-Estrada
- Laboratorio de Amibas Anfizóicas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, Mexico; (C.E.G.-E.); (D.H.-M.); (I.C.-R.)
| | - Anel Lagunes-Guillén
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de Mexico 07360, Mexico; (L.S.-V.); (B.C.-M.); (A.L.-G.)
| | - Dolores Hernández-Martínez
- Laboratorio de Amibas Anfizóicas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, Mexico; (C.E.G.-E.); (D.H.-M.); (I.C.-R.)
| | - Ismael Castelan-Ramírez
- Laboratorio de Amibas Anfizóicas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, Mexico; (C.E.G.-E.); (D.H.-M.); (I.C.-R.)
| | - Maritza Omaña-Molina
- Laboratorio de Amibas Anfizóicas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla 54090, Mexico; (C.E.G.-E.); (D.H.-M.); (I.C.-R.)
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Baroni L, Abreu-Filho PG, Pereira LM, Nagl M, Yatsuda AP. Recombinant actin-depolymerizing factor of the apicomplexan Neospora caninum (NcADF) is susceptible to oxidation. Front Cell Infect Microbiol 2022; 12:952720. [PMID: 36601306 PMCID: PMC9806845 DOI: 10.3389/fcimb.2022.952720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/21/2022] [Indexed: 12/24/2022] Open
Abstract
Neospora caninum is a member of Apicomplexa Phylum and the causative agent of neosporosis, a disease responsible for abortions in cattle. Apicomplexan parasites have a limited set of actin-binding proteins conducting the regulation of the dynamics of nonconventional actin. The parasite actin-based motility is implicated in the parasite invasion process in the host cell. Once no commercial strategy for the neosporosis control is available, the interference in the parasite actin function may result in novel drug targets. Actin-depolymerization factor (ADF) is a member of the ADF/cofilin family, primarily known for its function in actin severing and depolymerization. ADF/cofilins are versatile proteins modulated by different mechanisms, including reduction and oxidation. In apicomplexan parasites, the mechanisms involved in the modulation of ADF function are barely explored and the effects of oxidation in the protein are unknown so far. In this study, we used the oxidants N-chlorotaurine (NCT) and H2O2 to investigate the susceptibility of the recombinant N. caninum ADF (NcADF) to oxidation. After exposing the protein to either NCT or H2O2, the dimerization status and cysteine residue oxidation were determined. Also, the interference of NcADF oxidation in the interaction with actin was assessed. The treatment of the recombinant protein with oxidants reversibly induced the production of dimers, indicating that disulfide bonds between NcADF cysteine residues were formed. In addition, the exposure of NcADF to NCT resulted in more efficient oxidation of the cysteine residues compared to H2O2. Finally, the oxidation of NcADF by NCT reduced the ability of actin-binding and altered the function of NcADF in actin polymerization. Altogether, our results clearly show that recombinant NcADF is sensitive to redox conditions, indicating that the function of this protein in cellular processes involving actin dynamics may be modulated by oxidation.
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Affiliation(s)
- Luciana Baroni
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Péricles Gama Abreu-Filho
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Luiz Miguel Pereira
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Markus Nagl
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Ana Patricia Yatsuda
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil,*Correspondence: Ana Patricia Yatsuda,
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Current Opinion on the Therapeutic Capacity of Taurine-Containing Halogen Derivatives in Infectious and Inflammatory Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1370:83-98. [DOI: 10.1007/978-3-030-93337-1_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Mungroo MR, Khan NA, Maciver S, Siddiqui R. Opportunistic free-living amoebal pathogens. Pathog Glob Health 2021; 116:70-84. [PMID: 34602025 DOI: 10.1080/20477724.2021.1985892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Pathogenic free-living amoebae affecting the central nervous system are known to cause granulomatous amoebic encephalitis (GAE) or primary amoebic meningoencephalitis (PAM). Although hosts with impaired immunity are generally at a higher risk of severe disease, amoebae such as Naegleria fowleri and Balamuthia mandrillaris can instigate disease in otherwise immunocompetent individuals, whereas Acanthamoeba species mostly infect immunocompromised people. Acanthamoeba also cause a sight-threatening eye infection, mostly in contact lens wearers. Although infections due to pathogenic amoebae are considered rare, recently, these deadly amoebae were detected in water supplies in the USA. This is of particular concern, especially with global warming further exacerbating the problem. Herein, we describe the epidemiology, presentation, diagnosis, and management of free-living amoeba infections.
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Affiliation(s)
- Mohammad Ridwane Mungroo
- Department of Clinical Sciences, College of Medicine, University City, Sharjah, United Arab Emirates
| | - Naveed Ahmed Khan
- Department of Clinical Sciences, College of Medicine, University City, Sharjah, United Arab Emirates.,Research Institute of Health and Medical Sciences, University of Sharjah, Sharjah, UAE
| | - Sutherland Maciver
- Centre for Discovery Brain Sciences, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK
| | - Ruqaiyyah Siddiqui
- College of Arts and Sciences, American University of Sharjah, Sharjah, UAE
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Rice CA, Colon BL, Chen E, Hull MV, Kyle DE. Discovery of repurposing drug candidates for the treatment of diseases caused by pathogenic free-living amoebae. PLoS Negl Trop Dis 2020; 14:e0008353. [PMID: 32970675 PMCID: PMC7546510 DOI: 10.1371/journal.pntd.0008353] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 10/09/2020] [Accepted: 07/28/2020] [Indexed: 12/11/2022] Open
Abstract
Diseases caused by pathogenic free-living amoebae include primary amoebic meningoencephalitis (Naegleria fowleri), granulomatous amoebic encephalitis (Acanthamoeba spp.), Acanthamoeba keratitis, and Balamuthia amoebic encephalitis (Balamuthia mandrillaris). Each of these are difficult to treat and have high morbidity and mortality rates due to lack of effective therapeutics. Since repurposing drugs is an ideal strategy for orphan diseases, we conducted a high throughput phenotypic screen of 12,000 compounds from the Calibr ReFRAME library. We discovered a total of 58 potent inhibitors (IC50 <1 μM) against N. fowleri (n = 19), A. castellanii (n = 12), and B. mandrillaris (n = 27) plus an additional 90 micromolar inhibitors. Of these, 113 inhibitors have never been reported to have activity against Naegleria, Acanthamoeba or Balamuthia. Rapid onset of action is important for new anti-amoeba drugs and we identified 19 compounds that inhibit N. fowleri in vitro within 24 hours (halofuginone, NVP-HSP990, fumagillin, bardoxolone, belaronib, and BPH-942, solithromycin, nitracrine, quisinostat, pabinostat, pracinostat, dacinostat, fimepinostat, sanguinarium, radicicol, acriflavine, REP3132, BC-3205 and PF-4287881). These compounds inhibit N. fowleri in vitro faster than any of the drugs currently used for chemotherapy. The results of these studies demonstrate the utility of phenotypic screens for discovery of new drugs for pathogenic free-living amoebae, including Acanthamoeba for the first time. Given that many of the repurposed drugs have known mechanisms of action, these compounds can be used to validate new targets for structure-based drug design.
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Affiliation(s)
- Christopher A. Rice
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- * E-mail: (CAR); (DEK)
| | - Beatrice L. Colon
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Emily Chen
- Calibr at Scripps Research, La Jolla, California, United States of America
| | - Mitchell V. Hull
- Calibr at Scripps Research, La Jolla, California, United States of America
| | - Dennis E. Kyle
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, United States of America
- * E-mail: (CAR); (DEK)
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Mungroo MR, Anwar A, Khan NA, Siddiqui R. Brain-eating Amoebae Infection: Challenges and Opportunities in Chemotherapy. Mini Rev Med Chem 2019; 19:980-987. [PMID: 30868950 DOI: 10.2174/1389557519666190313161854] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/01/2019] [Accepted: 03/07/2019] [Indexed: 12/22/2022]
Abstract
Pathogenic free-living amoeba are known to cause a devastating infection of the central nervous system and are often referred to as "brain-eating amoebae". The mortality rate of more than 90% and free-living nature of these amoebae is a cause for concern. It is distressing that the mortality rate has remained the same over the past few decades, highlighting the lack of interest by the pharmaceutical industry. With the threat of global warming and increased outdoor activities of public, there is a need for renewed interest in identifying potential anti-amoebic compounds for successful prognosis. Here, we discuss the available chemotherapeutic options and opportunities for potential strategies in the treatment and diagnosis of these life-threatening infections.
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Affiliation(s)
- Mohammad Ridwane Mungroo
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya 47500, Selangor, Malaysia
| | - Ayaz Anwar
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya 47500, Selangor, Malaysia
| | - Naveed Ahmed Khan
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya 47500, Selangor, Malaysia
| | - Ruqaiyyah Siddiqui
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya 47500, Selangor, Malaysia
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Teuchner B, Wibmer ID, Schaumann P, Seifarth C, Walochnik J, Nagl M. N-chlorotaurine Inactivates Acanthamoeba and Candida albicans in the Porcine Ex Vivo Corneal Infection Model. Cornea 2019; 38:1011-1016. [DOI: 10.1097/ico.0000000000001927] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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N-Chlorotaurine, a Promising Future Candidate for Topical Therapy of Fungal Infections. Mycopathologia 2017; 183:161-170. [PMID: 28702855 PMCID: PMC5773618 DOI: 10.1007/s11046-017-0175-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/29/2017] [Indexed: 12/21/2022]
Abstract
N-Chlorotaurine (NCT) is a mild long-lived oxidant that can be applied to sensitive body regions as an endogenous antiseptic. Enhancement of its microbicidal activity in the presence of proteinaceous material because of transchlorination, a postantibiotic/postantifungal effect and antitoxic activity renders it interesting for treatment of fungal infections, too. This is confirmed by first case applications in skin and mucous membranes of different body sites. Recent findings of good tolerability of inhaled NCT suggest further investigations of this substance for treatment of bronchopulmonary diseases, where microorganisms play a role, particularly multi-resistant ones. The availability of a well-tolerated and effective inhaled antiseptic with anti-inflammatory properties could be a significant progress, in particular for chronic pulmonary diseases, such as chronic obstructive pulmonary disease or cystic fibrosis.
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Heredero-Bermejo I, Copa-Patiño JL, Soliveri J, Fuentes-Paniagua E, de la Mata FJ, Gomez R, Perez-Serrano J. Evaluation of the activity of new cationic carbosilane dendrimers on trophozoites and cysts of Acanthamoeba polyphaga. Parasitol Res 2014; 114:473-86. [PMID: 25358240 DOI: 10.1007/s00436-014-4205-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 10/22/2014] [Indexed: 01/16/2023]
Abstract
Dendrimers are repetitively branched molecules with a broad spectrum of applications, mainly for their antimicrobial properties and as nanocarriers for other molecules. Recently, our research group have synthesized and studied their activity against Acanthamoeba sp., causative agent of a severe ocular disease in humans: Acanthamoeba keratitis. New cationic carbosilane dendrimers were tested against the protozoa forms at different concentrations and for different incubation times. Trophozoite viability was determined by manual counting and cyst viability by observing excystment in microplates with fresh culture medium. Cytotoxicity was checked on HeLa cells using the microculture tetrazolium assay. Alterations were observed by optical microscopy and by flow cytometry staining with propidium iodide. Six out of the 18 dendrimers tested were non-cytotoxic and effective against the trophozoite form, having one of them (dendrimer 14 with an IC50 of 2.4 + 0.1 mg/L) a similar activity to chlorhexidine digluconate (IC50 1.7 + 0.1 mg/L). This dendrimer has a polyphenoxo core and a sulphur atom close to the six -NH3+ terminal groups. On the other hand, only two dendrimers showed some effect against cysts (dendrimers 14 and 17). However, their minimum cysticidal concentrations were cytotoxic and less effective than the control drug. The alterations on the amoeba morphology produced by the treatment with dendrimers were size reduction, increased complexity, loss of acanthopodia and cell membrane disruption. In conclusion, these results suggest that some dendrimers may be studied in animal models to test their effect and that new dendrimers with similar features should be synthesized.
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Affiliation(s)
- Irene Heredero-Bermejo
- Departamento de Biomedicina y Biotecnología, Universidad de Alcalá, Alcalá de Henares, Spain,
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Heredero-Bermejo I, Copa-Patiño JL, Soliveri J, Gómez R, de la Mata FJ, Pérez-Serrano J. In vitro comparative assessment of different viability assays in Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites. Parasitol Res 2013; 112:4087-95. [PMID: 24026387 DOI: 10.1007/s00436-013-3599-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 08/25/2013] [Indexed: 01/30/2023]
Abstract
The species of the genus Acanthamoeba are opportunistic protozoan parasites that cause different diseases in humans, such as amoebic keratitis and granulomatous encephalitis. The rise in the rate of Acanthamoeba keratitis, mainly due to the increase in contact lens wearers, turns the development of viability assays using a multi-well plate reader as a tool for screening new antiamoebic agents in vitro into an important goal. In our study, the viability assays PrestoBlue®, resazurin sodium salt, 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) and CellTiter96® were tested for their suitability as time-saving alternatives to the classical manual or direct-counting method, assessing the effect of the antiamoebic agent chlorhexidine digluconate and temperature on Acanthamoeba castellanii (ATCC® 30234™) and Acanthamoeba polyphaga 2961. Although resazurin and MTT have already been previously used in amoeba viability assays to test the activities of antiamoebic agents in vitro, it is the first time that PrestoBlue® and CellTiter96® are used for this purpose. Results indicated that the viability assays were strain-dependent leading in some cases to an overestimation of the real situation of viable cells. This implies that each viability assay ought to be set up for each amoeba strain studied.
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Affiliation(s)
- I Heredero-Bermejo
- Department of Biomedicine and Biotechnology, School of Pharmacy, University of Alcalá, Ctra. Madrid-Barcelona (Autovía A2) Km. 33 600, 28871, Alcalá de Henares, Madrid, Spain
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Heredero-Bermejo I, Copa-Patiño JL, Soliveri J, García-Gallego S, Rasines B, Gómez R, de la Mata FJ, Pérez-Serrano J. In vitro evaluation of the effectiveness of new water-stable cationic carbosilane dendrimers against Acanthamoeba castellanii UAH-T17c3 trophozoites. Parasitol Res 2012; 112:961-9. [PMID: 23263327 DOI: 10.1007/s00436-012-3216-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 11/22/2012] [Indexed: 10/27/2022]
Abstract
Acanthamoeba is one of the most common free-living amoebas which is widespread in the environment and can infect humans, causing diseases such as keratitis and encephalitis. In this paper we examine for the first time the amebicidal activity of the family of cationic dendrimers nG-[Si{(CH(2))(3)N(+)(Me)(Et)(CH(2))(2)NMe(3) (+)}2I(-)]( x ) (where n denotes the generations: zero (n = 0, x = 1), first (n = 1, x = 4), and second (n = 2, x = 8); for simplicity, they were named as 0G-CNN2, 1G-CNN8, and 2G-CNN16, respectively) against Acanthamoeba castellanii UAH-T17c3 trophozoites. In order to test the amebicidal activity, we cultured the strain A. castellanii UAH-T17c3 in PYG-Bactocasitone medium and later, we treated it with different concentrations of these dendrimers and monitored the effects and damage by optical count, flow cytometry, and scanning electron microscopy. The results showed that all the nanosystems assayed had a strong amebicidal activity. The dendrimer 1G-CNN8 was the most effective against the amoeba. In the morphology of treated throphozoites of A. castellanii UAH-T17c3 analyzed by light and scanning electron microscopy techniques, morphological changes were evident in amoeba cells, such as loss of pseudopodia, ectoplasm increase, roundness, and cellular lysis. Furthermore, flow cytometry results showed alterations in cell granularity, which was dose-time dependent. In conclusion, this family of cationic carbosilane dendrimers has a strong amebicidal activity against the trophozoites of A. castellanii UAH-T17c3 in vitro. They could potentially become new agents significant to the development of new amebicidal compounds for prevention and therapy of Acanthamoeba infections.
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Affiliation(s)
- I Heredero-Bermejo
- Department of Microbiology and Parasitology, University of Alcalá, Ctra Madrid-Barcelona (Autovía A2) Km 33,600, 28871, Alcalá de Henares, Madrid, Spain
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[Therapy-resistant otitis externa with additional tympanic membrane perforation: local therapy using N-chlorotaurine and dexamethasone]. HNO 2011; 58:927-30. [PMID: 20730412 DOI: 10.1007/s00106-010-2082-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Ear canal infections may not always be clinically distinguished between a bacterial otitis externa, an otomycosis or a mixed infection. In addition, tympanic membrane perforations are often not immediately apparent. The use of a broad-spectrum antiseptic agent without an inner ear toxic effect would therefore be beneficial. We report the case of a female patient suffering from intractable otitis externa with tympanic membrane perforation, who was successfully treated locally with a mixture of 1% NCT and 0.1% dexamethasone.
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Islambulchilar M, Sattari MR, Sardashti M, Lotfipour F. Effect of Taurine on the antimicrobial efficiency of Gentamicin. Adv Pharm Bull 2011; 1:69-74. [PMID: 24312759 DOI: 10.5681/apb.2011.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 11/10/2011] [Indexed: 01/15/2023] Open
Abstract
CONTEXT Gentamicin is mainly used in severe infections caused by gram-negatives. However toxicity including nephrotoxicity and ototoxicity is one of the most important complications of its treatment. The production of free radicals seems to be involved in gentamicin toxicity mechanism. Taurine, a major intracellular free β-amino acid, is known to be an endogenous antioxidant. So potentially the co-therapy of taurine and gentamicin would reduce the adverse effects of the antibiotic. OBJECTIVES In this study, we wished to know the effect of taurine on the antibiotic capacity of gentamicin. METHODS strainsof P. aeruginosa, E. coli, S. aureus and S. epidermidis were used as test organisms. Minimum inhibitory concentrations of gentamicin in the presence and absence of taurine at quantities from 40 to 2 mg/L were determined using macro-dilution method. RESULTS MICs were determined in the various concentrations of taurine for bacterial indicators. The MIC values of gentamicin for P. aeruginosa, S. aureus and E. coli remained unchanged in the values of 2.5, 5 and 20 μg/ml respectively in the absence and presences of different concentrations of taurine. The bactericidal activity of gentamicin against S. epidermidis was increased by addition of taurine in the concentrations higher than 6 mg/L. CONCLUSION According to our study the antibacterial activity of gentamicin against the indicator microorganisms were not interfere with taurine at selected concentrations. Further in vivo studies are needed to establish if a combination of gentamicin and taurine would have the same effect.
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Affiliation(s)
- Mina Islambulchilar
- School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran ; Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran ; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
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Fürnkranz U, Nagl M, Gottardi W, Duchêne M, Aspöck H, Walochnik J. In vitro activity of N-chlorotaurine (NCT) in combination with NH4Cl against Trichomonas vaginalis. Int J Antimicrob Agents 2010; 37:171-3. [PMID: 21074373 PMCID: PMC3030749 DOI: 10.1016/j.ijantimicag.2010.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Revised: 08/26/2010] [Accepted: 09/18/2010] [Indexed: 10/28/2022]
Abstract
Trichomoniasis, caused by the protozoan Trichomonas vaginalis, is usually treated with metronidazole, however resistance is on the rise. In this study, N-chlorotaurine (NCT), a new endogenous mild active chlorine compound for topical use, killed T. vaginalis in vitro within 15 min of treatment at a concentration of 55 mM (1%), which is well tolerated by human tissue. The activity of NCT was further enhanced by addition of ammonium chloride (NH(4)Cl). A combination of 5.5 mM (0.1%) NCT plus 19 mM (0.1%) NH(4)Cl killed 100% of trichomonads within 5 min.
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Affiliation(s)
- Ursula Fürnkranz
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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Gottardi W, Nagl M. N-chlorotaurine, a natural antiseptic with outstanding tolerability. J Antimicrob Chemother 2010; 65:399-409. [PMID: 20053689 DOI: 10.1093/jac/dkp466] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
N-chlorotaurine, the N-chloro derivative of the amino acid taurine, is a long-lived oxidant produced by activated human granulocytes and monocytes. Supported by a high number of in vitro studies, it has mainly anti-inflammatory properties and seems to be involved in the termination of inflammation. The successful synthesis of the crystalline sodium salt (Cl-HN-CH(2)-CH(2)-SO(3)Na, NCT) facilitated its development as an endogenous antiseptic. NCT can be stored long-term at low temperatures, and it has killing activity against bacteria, fungi, viruses and parasites. Transfer of the active chlorine to amino groups of molecules of both the pathogens and the human body (transhalogenation) enhances rather than decreases its activity, mainly because of the formation of monochloramine. Furthermore, surface chlorination after sublethal incubation times in NCT leads to a post-antibiotic effect and loss of virulence of pathogens, as demonstrated for bacteria and yeasts. Being a mild oxidant, NCT proved to be very well tolerated by human tissue in Phase I and II clinical studies. A 1% aqueous solution can be applied to the eye, skin ulcerations, outer ear canal, nasal and paranasal sinuses, oral cavity and urinary bladder, and can probably be used for inhalation. Therapeutic efficacy in Phase II studies has been shown in external otitis, purulently coated crural ulcerations and keratoconjunctivitis, so far. Based upon all presently available data, NCT seems to be an antiseptic with a very good relation between tolerability and activity. Recently, C-methylated derivatives of NCT have been invented, which are of interest because of improved stability at room temperature.
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Affiliation(s)
- Waldemar Gottardi
- Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Innsbruck Medical University, A-6020 Innsbruck, Austria
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Lukáč M, Mrva M, Fischer-Fodor E, Lacko I, Bukovský M, Miklášová N, Ondriska F, Devínsky F. Synthesis and biological activity of dialkylphosphocholines. Bioorg Med Chem Lett 2009; 19:6346-9. [DOI: 10.1016/j.bmcl.2009.09.079] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Revised: 09/18/2009] [Accepted: 09/20/2009] [Indexed: 10/20/2022]
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Fürnkranz U, Nagl M, Gottardi W, Matt U, Aspöck H, Walochnik J. N-Chlorotaurine shows high in vitro activity against promastigotes and amastigotes of Leishmania species. J Med Microbiol 2009; 58:1298-1302. [DOI: 10.1099/jmm.0.011155-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protozoan parasites of the genus Leishmania are the causative agents of life-threatening visceral as well as cutaneous and mucocutaneous leishmaniasis. First-line drugs are antimonials, but toxicity and resistance in some endemic areas cause serious problems. In the current study, the antileishmanial activity of the weak oxidant N-chlorotaurine (NCT) was investigated. NCT is a derivative of the amino acid taurine produced by granulocytes and monocytes during oxidative burst, but can also be synthesized chemically and used topically as an antiseptic at a concentration of 1 % (55 mM) in vivo. NCT susceptibility tests were performed in vitro with promastigotes and amastigotes of Leishmania infantum and Leishmania donovani. As NH4Cl is known to increase the activity of NCT by the formation of monochloramine (NH2Cl), co-treatment assays were included in the study. Mean EC50 values after 1 h of treatment were 5.94 mM for L. infantum and 9.8 mM for L. donovani promastigotes. Co-treatment with 5.5 mM NCT plus 19 mM NH4Cl led to complete killing of promastigotes of both strains within 15 min. Amastigotes were inactivated by treatment with 2 mM NCT alone. The results of this study indicate a high potential of NCT against Leishmania species.
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Affiliation(s)
- Ursula Fürnkranz
- Department of Medical Parasitology, Clinical Institute of Hygiene and Medical Microbiology, Medical University of Vienna, Kinderspitalgasse 15, 1095 Vienna, Austria
| | - Markus Nagl
- Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Fritz-Pregl-Strasse 3, 6020 Innsbruck, Austria
| | - Waldemar Gottardi
- Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Fritz-Pregl-Strasse 3, 6020 Innsbruck, Austria
| | - Ulrich Matt
- Research Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM), Vienna, Austria
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Horst Aspöck
- Department of Medical Parasitology, Clinical Institute of Hygiene and Medical Microbiology, Medical University of Vienna, Kinderspitalgasse 15, 1095 Vienna, Austria
| | - Julia Walochnik
- Department of Medical Parasitology, Clinical Institute of Hygiene and Medical Microbiology, Medical University of Vienna, Kinderspitalgasse 15, 1095 Vienna, Austria
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Koehsler M, Leitsch D, Duchêne M, Nagl M, Walochnik J. Acanthamoeba castellanii : growth on human cell layers reactivates attenuated properties after prolonged axenic culture. FEMS Microbiol Lett 2009; 299:121-7. [PMID: 19732153 PMCID: PMC2810444 DOI: 10.1111/j.1574-6968.2009.01680.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The free-living, but potentially pathogenic, bacteriovorous amoebae of the genus Acanthamoeba can be easily grown axenically in a laboratory culture. This, however, often leads to considerable losses in virulence, and encystment capacity, and to changes in drug susceptibility. We evaluated potential options for a reactivation of a number of physiological properties, attenuated by prolonged axenic laboratory culture, including encystment potential, protease activity, heat resistance, growth rates and drug susceptibility against N-chlorotaurine (NCT). Toward this end, a strain that had been grown axenically for 10 years was repeatedly passaged on human HEp-2 cell monolayers or treated with 5′-azacytidine (AzaC), a methyltransferase inhibitor, and trichostatin A (TSA), a histone deacetylase inhibitor, in order to uplift epigenetic gene regulation. Culture on human cell monolayers resulted in significantly enhanced encystment potentials and protease activities, and higher susceptibility against NCT, whereas the resistance against heat shock was not altered. Treatment with AzaC/TSA resulted in increased encystment rates and protease activities, indicating the participation of epigenetic mechanisms. However, lowered resistances against heat shock indicate that possible stress responses to AzaC/TSA have to be taken into account. Repeated growth on human cell monolayers appears to be a potential method to reactivate attenuated characteristics in Acanthamoeba.
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Affiliation(s)
- Martina Koehsler
- Department of Medical Parasitology, Clinical Institute of Hygiene and Medical Microbiology, Medical University of Vienna, Kinderspitalgasse 15, Vienna, Austria
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