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Prates RA, Fuchs BB, Mizuno K, Naqvi Q, Kato IT, Ribeiro MS, Mylonakis E, Tegos GP, Hamblin MR. Effect of virulence factors on the photodynamic inactivation of Cryptococcus neoformans. PLoS One 2013; 8:e54387. [PMID: 23349872 PMCID: PMC3548784 DOI: 10.1371/journal.pone.0054387] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 12/11/2012] [Indexed: 02/07/2023] Open
Abstract
Opportunistic fungal pathogens may cause an array of superficial infections or serious invasive infections, especially in immunocompromised patients. Cryptococcus neoformans is a pathogen causing cryptococcosis in HIV/AIDS patients, but treatment is limited due to the relative lack of potent antifungal agents. Photodynamic inactivation (PDI) uses the combination of non-toxic dyes called photosensitizers and harmless visible light, which produces singlet oxygen and other reactive oxygen species that produce cell inactivation and death. We report the use of five structurally unrelated photosensitizers (methylene blue, Rose Bengal, selenium derivative of a Nile blue dye, a cationic fullerene and a conjugate between poly-L-lysine and chlorin(e6)) combined with appropriate wavelengths of light to inactivate C. neoformans. Mutants lacking capsule and laccase, and culture conditions that favoured melanin production were used to probe the mechanisms of PDI and the effect of virulence factors. The presence of cell wall, laccase and melanin tended to protect against PDI, but the choice of the appropriate photosensitizers and dosimetry was able to overcome this resistance.
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Affiliation(s)
- Renato A. Prates
- Center for Lasers and Applications, Nuclear and Energy Research Institute, São Paulo, SP, Brazil
- School of Dentistry, Health Department, Universidade Nove de Julho, São Paulo, SP, Brazil
- Wellman Center of Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Beth Burgwyn Fuchs
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Kazue Mizuno
- Wellman Center of Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Qurat Naqvi
- Wellman Center of Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Ilka T. Kato
- Center for Lasers and Applications, Nuclear and Energy Research Institute, São Paulo, SP, Brazil
| | - Martha S. Ribeiro
- Center for Lasers and Applications, Nuclear and Energy Research Institute, São Paulo, SP, Brazil
| | - Eleftherios Mylonakis
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - George P. Tegos
- Wellman Center of Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Pathology, University of New Mexico School of Medicine, New Mexico, United States of America
- * E-mail: (GPT); (MH)
| | - Michael R. Hamblin
- Wellman Center of Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, United States of America
- Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Cambridge, Massachusetts, United States of America
- * E-mail: (GPT); (MH)
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Kato IT, Prates RA, Sabino CP, Fuchs BB, Tegos GP, Mylonakis E, Hamblin MR, Ribeiro MS. Antimicrobial photodynamic inactivation inhibits Candida albicans virulence factors and reduces in vivo pathogenicity. Antimicrob Agents Chemother 2013; 57:445-51. [PMID: 23129051 PMCID: PMC3535901 DOI: 10.1128/aac.01451-12] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Accepted: 10/29/2012] [Indexed: 01/01/2023] Open
Abstract
The objective of this study was to evaluate whether Candida albicans exhibits altered pathogenicity characteristics following sublethal antimicrobial photodynamic inactivation (APDI) and if such alterations are maintained in the daughter cells. C. albicans was exposed to sublethal APDI by using methylene blue (MB) as a photosensitizer (0.05 mM) combined with a GaAlAs diode laser (λ 660 nm, 75 mW/cm(2), 9 to 27 J/cm(2)). In vitro, we evaluated APDI effects on C. albicans growth, germ tube formation, sensitivity to oxidative and osmotic stress, cell wall integrity, and fluconazole susceptibility. In vivo, we evaluated C. albicans pathogenicity with a mouse model of systemic infection. Animal survival was evaluated daily. Sublethal MB-mediated APDI reduced the growth rate and the ability of C. albicans to form germ tubes compared to untreated cells (P < 0.05). Survival of mice systemically infected with C. albicans pretreated with APDI was significantly increased compared to mice infected with untreated yeast (P < 0.05). APDI increased C. albicans sensitivity to sodium dodecyl sulfate, caffeine, and hydrogen peroxide. The MIC for fluconazole for C. albicans was also reduced following sublethal MB-mediated APDI. However, none of those pathogenic parameters was altered in daughter cells of C. albicans submitted to APDI. These data suggest that APDI may inhibit virulence factors and reduce in vivo pathogenicity of C. albicans. The absence of alterations in daughter cells indicates that APDI effects are transitory. The MIC reduction for fluconazole following APDI suggests that this antifungal could be combined with APDI to treat C. albicans infections.
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Affiliation(s)
- Ilka Tiemy Kato
- Center for Lasers and Applications, IPEN-CNEN/SP, São Paulo, Brazil
| | - Renato Araujo Prates
- Center for Lasers and Applications, IPEN-CNEN/SP, São Paulo, Brazil
- Dentistry School, Health Division and Biophotonics Program of UNINOVE, São Paulo, São Paulo, Brazil
| | | | - Beth Burgwyn Fuchs
- Harvard Medical School, Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - George P. Tegos
- Department of Pathology, School of Medicine, and Center for Molecular Discovery, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, USA
| | - Eleftherios Mylonakis
- Harvard Medical School, Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Michael R. Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, USA
- Harvard—MIT Division of Health Sciences and Technology, Cambridge, Massachusetts, USA
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53
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Rodrigues GB, Dias-Baruffi M, Holman N, Wainwright M, Braga GUL. In vitro photodynamic inactivation of Candida species and mouse fibroblasts with phenothiazinium photosensitisers and red light. Photodiagnosis Photodyn Ther 2012; 10:141-9. [PMID: 23769280 DOI: 10.1016/j.pdpdt.2012.11.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 10/24/2012] [Accepted: 11/01/2012] [Indexed: 10/27/2022]
Abstract
In the present study, the in vitro susceptibilities of five Candida spp. to photodynamic antimicrobial chemotherapy (PACT) with four phenothiazinium derivatives, methylene blue (MB), new methylene blue N (NMBN), toluidine blue O (TBO) and the novel pentacyclic phenothiazinium photosensitiser S137, in combination with red light were investigated. The efficacy of each PS was determined, initially, based on its minimal inhibitory concentration (MIC). Additionally, we evaluated the effect of the photodynamic treatment with NMBN and S137 on Candida survival and on the mouse fibroblast cell line L929. MICs varied both among PS and species and decreased with light dose increase. For most treatments (species and fluences) NMBN and S137 showed the lowest MICs. MICs for NMBN and S137 were <2.5 μM for all the Candida species when a fluence of 25 J cm⁻² was used. PACT with NMBN (fluence of 15 J cm⁻²) resulted in reductions in survival from 0.3 log (Candida krusei) to 3 logs (C. parapsilosis). PACT with S137 was more effective than with NMBN. Fluence of 15 J cm⁻² resulted in reductions in survival from 1 log (C. krusei) to 3 logs (C. parapsilosis) and fluence of 25 J cm⁻² resulted in a reduction of approximately 2 logs (C. krusei) and between 3 and 4 logs in survival of the other 4 species of Candida. In vitro relative toxicities of the phenothiazinium PS to mammalian cells exhibited a similar trend to the antifungal data, i.e. greater toxicity and phototoxicity with NMBN and S137 compared to the established PS.
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Affiliation(s)
- Gabriela B Rodrigues
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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54
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Susceptibilities of the dermatophytes Trichophyton mentagrophytes and T. rubrum microconidia to photodynamic antimicrobial chemotherapy with novel phenothiazinium photosensitizers and red light. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 116:89-94. [DOI: 10.1016/j.jphotobiol.2012.08.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 08/01/2012] [Accepted: 08/08/2012] [Indexed: 11/22/2022]
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Dai T, Fuchs BB, Coleman JJ, Prates RA, Astrakas C, St Denis TG, Ribeiro MS, Mylonakis E, Hamblin MR, Tegos GP. Concepts and principles of photodynamic therapy as an alternative antifungal discovery platform. Front Microbiol 2012; 3:120. [PMID: 22514547 PMCID: PMC3322354 DOI: 10.3389/fmicb.2012.00120] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Accepted: 03/13/2012] [Indexed: 01/25/2023] Open
Abstract
Opportunistic fungal pathogens may cause superficial or serious invasive infections, especially in immunocompromised and debilitated patients. Invasive mycoses represent an exponentially growing threat for human health due to a combination of slow diagnosis and the existence of relatively few classes of available and effective antifungal drugs. Therefore systemic fungal infections result in high attributable mortality. There is an urgent need to pursue and deploy novel and effective alternative antifungal countermeasures. Photodynamic therapy (PDT) was established as a successful modality for malignancies and age-related macular degeneration but photodynamic inactivation has only recently been intensively investigated as an alternative antimicrobial discovery and development platform. The concept of photodynamic inactivation requires microbial exposure to either exogenous or endogenous photosensitizer molecules, followed by visible light energy, typically wavelengths in the red/near infrared region that cause the excitation of the photosensitizers resulting in the production of singlet oxygen and other reactive oxygen species that react with intracellular components, and consequently produce cell inactivation and death. Antifungal PDT is an area of increasing interest, as research is advancing (i) to identify the photochemical and photophysical mechanisms involved in photoinactivation; (ii) to develop potent and clinically compatible photosensitizers; (iii) to understand how photoinactivation is affected by key microbial phenotypic elements multidrug resistance and efflux, virulence and pathogenesis determinants, and formation of biofilms; (iv) to explore novel photosensitizer delivery platforms; and (v) to identify photoinactivation applications beyond the clinical setting such as environmental disinfectants.
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Affiliation(s)
- Tianhong Dai
- Wellman Center for Photomedicine, Massachusetts General Hospital Boston, MA, USA
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56
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Hashimoto MCE, Prates RA, Kato IT, Núñez SC, Courrol LC, Ribeiro MS. Antimicrobial photodynamic therapy on drug-resistant Pseudomonas aeruginosa-induced infection. An in vivo study. Photochem Photobiol 2012; 88:590-5. [PMID: 22404212 DOI: 10.1111/j.1751-1097.2012.01137.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pseudomonas aeruginosa is considered one of the most important pathogens that represent life-threatening risk in nosocomial environments, mainly in patients with severe burns. Antimicrobial photodynamic therapy (aPDT) has been effective to kill bacteria. The purpose of this study was to develop a burn wound and bloodstream infection model and verify aPDT effects on it. In vitro, we tested two wavelengths (blue and red LEDs) on a clinical isolate of P. aeruginosa strain with resistance to multiple antibiotics using HB:La(+3) as photosensitizer. Verapamil(®) associated to aPDT was also studied. In vivo, P. aeruginosa-infected burned mice were submitted to aPDT. Bacterial counting was performed on local infection and bloodstream. Survival time of animals was also monitored. In this study, aPDT was effective to reduce P. aeruginosa in vitro. In addition, Verapamil(®) assay showed that HB:La(+3) is not recognized by ATP-binding cassete (ABC) efflux pump mechanism. In the in vivo study, aPDT was able to reduce bacterial load in burn wounds, delay bacteremia and keep the bacterial levels in blood 2-3 logs lower compared with an untreated group. Mice survival was increased on 24 h. Thus, this result suggests that aPDT may also be a novel prophylactic treatment in the care of burned patients.
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Affiliation(s)
- Maria C E Hashimoto
- Center for Lasers and Applications, Institute of Energetic and Nuclear Researches, IPEN-CNEN/SP, São Paulo, SP, Brazil
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57
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Almeida LM, Zanoelo FF, Castro KP, Borissevitch IE, Soares CMA, Gonçalves PJ. Cell Survival and Altered Gene Expression Following Photodynamic Inactivation of Paracoccidioides brasiliensis. Photochem Photobiol 2012; 88:992-1000. [DOI: 10.1111/j.1751-1097.2012.01112.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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58
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Abstract
The growing resistance against antifungal drugs has renewed the search for alternative treatment modalities, and antimicrobial photodynamic therapy (PDT) seems to be a potential candidate. Preliminary findings have demonstrated that dermatophytes and yeasts can be effectively sensitized in vitro and in vivo by administering photosensitizers (PSs) belonging to four chemical groups: phenothiazine dyes, porphyrins and phthalocyanines, as well as aminolevulinic acid, which, while not a PS in itself, is effectively metabolized into protoporphyrin IX. Besides efficacy, PDT has shown other benefits. First, the sensitizers used are highly selective, i.e., fungi can be killed at combinations of drug and light doses much lower than that needed for a similar effect on keratinocytes. Second, all investigated PSs lack genotoxic and mutagenic activity. Finally, the hazard of selection of drug resistant fungal strains has been rarely reported. We review the studies published to date on antifungal applications of PDT, with special focus on yeast, and aim to raise awareness of this area of research, which has the potential to make a significant impact in future treatment of fungal infections.
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Vera DMA, Haynes MH, Ball AR, Dai T, Astrakas C, Kelso MJ, Hamblin MR, Tegos GP. Strategies to potentiate antimicrobial photoinactivation by overcoming resistant phenotypes. Photochem Photobiol 2012; 88:499-511. [PMID: 22242675 DOI: 10.1111/j.1751-1097.2012.01087.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Conventional antimicrobial strategies have become increasingly ineffective due to the emergence of multidrug resistance among pathogenic microorganisms. The need to overcome these deficiencies has triggered the exploration of alternative treatments and unconventional approaches towards controlling microbial infections. Photodynamic therapy (PDT) was originally established as an anticancer modality and is currently used in the treatment of age-related macular degeneration. The concept of photodynamic inactivation requires cell exposure to light energy, typically wavelengths in the visible region that causes the excitation of photosensitizer molecules either exogenous or endogenous, which results in the production of reactive oxygen species (ROS). ROS produce cell inactivation and death through modification of intracellular components. The versatile characteristics of PDT prompted its investigation as an anti-infective discovery platform. Advances in understanding of microbial physiology have shed light on a series of pathways, and phenotypes that serve as putative targets for antimicrobial drug discovery. Investigations of these phenotypic elements in concert with PDT have been reported focused on multidrug efflux systems, biofilms, virulence and pathogenesis determinants. In many instances the results are promising but only preliminary and require further investigation. This review discusses the different antimicrobial PDT strategies and highlights the need for highly informative and comprehensive discovery approaches.
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Affiliation(s)
- Domingo Mariano Adolfo Vera
- Department of Chemistry, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
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60
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Baptista A, Kato IT, Prates RA, Suzuki LC, Raele MP, Freitas AZ, Ribeiro MS. Antimicrobial Photodynamic Therapy as a Strategy to Arrest Enamel Demineralization: A Short-Term Study on Incipient Caries in a Rat Model†. Photochem Photobiol 2012; 88:584-9. [DOI: 10.1111/j.1751-1097.2011.01059.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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61
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Pereira Gonzales F, Maisch T. Photodynamic inactivation for controlling Candida albicans infections. Fungal Biol 2012; 116:1-10. [DOI: 10.1016/j.funbio.2011.10.001] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 10/07/2011] [Accepted: 10/10/2011] [Indexed: 01/04/2023]
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Snell SB, Foster TH, Haidaris CG. Miconazole induces fungistasis and increases killing of Candida albicans subjected to photodynamic therapy. Photochem Photobiol 2011; 88:596-603. [PMID: 22077904 DOI: 10.1111/j.1751-1097.2011.01039.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cutaneous and mucocutaneous Candida infections are considered to be important targets for antimicrobial photodynamic therapy (PDT). Clinical application of antimicrobial PDT will require strategies that enhance microbial killing while minimizing damage to host tissue. Increasing the sensitivity of infectious agents to PDT will help achieve this goal. Our previous studies demonstrated that raising the level of oxidative stress in Candida by interfering with fungal respiration increased the efficiency of PDT. Therefore, we sought to identify compounds in clinical use that would augment the oxidative stress caused by PDT by contributing to reactive oxygen species (ROS) formation themselves. Based on the ability of the antifungal miconazole to induce ROS in Candida, we tested several azole antifungals for their ability to augment PDT in vitro. Although miconazole and ketoconazole both stimulated ROS production in Candida albicans, only miconazole enhanced the killing of C. albicans and induced prolonged fungistasis in organisms that survived PDT using the porphyrin TMP-1363 and the phenothiazine methylene blue as photosensitizers. The data suggest that miconazole could be used to increase the efficacy of PDT against C. albicans, and its mechanism of action is likely to be multifactorial.
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Affiliation(s)
- Sara B Snell
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY, USA
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63
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St Denis TG, Dai T, Izikson L, Astrakas C, Anderson RR, Hamblin MR, Tegos GP. All you need is light: antimicrobial photoinactivation as an evolving and emerging discovery strategy against infectious disease. Virulence 2011; 2:509-20. [PMID: 21971183 DOI: 10.4161/viru.2.6.17889] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The story of prevention and control of infectious diseases remains open and a series of highly virulent pathogens are emerging both in and beyond the hospital setting. Antibiotics were an absolute success story for a previous era. The academic and industrial biomedical communities have now come together to formulate consensus beliefs regarding the pursuit of novel and effective alternative anti-infective countermeasures. Photodynamic therapy was established and remains a successful modality for malignancies but photodynamic inactivation has been transformed recently to an antimicrobial discovery and development platform. The concept of photodynamic inactivation is quite straightforward and requires microbial exposure to visible light energy, typically wavelengths in the visible region, that causes the excitation of photosensitizer molecules (either exogenous or endogenous), which results in the production of singlet oxygen and other reactive oxygen species that react with intracellular components, and consequently produce cell inactivation. It is an area of increasing interest, as research is advancing i) to identify the photochemical and photophysical mechanisms involved in inactivation; ii) to develop potent and clinically compatible photosensitizer; iii) to understand how photoinactivation is affected by key microbial phenotypic elements (multidrug resistance and efflux, virulence and pathogenesis determinants, biofilms); iv) to explore novel delivery platforms inspired by current trends in pharmacology and nanotechnology; and v) to identify photoinactivation applications beyond the clinical setting such as environmental disinfectants.
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Affiliation(s)
- Tyler G St Denis
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, USA
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64
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Blue dye and red light, a dynamic combination for prophylaxis and treatment of cutaneous Candida albicans infections in mice. Antimicrob Agents Chemother 2011; 55:5710-7. [PMID: 21930868 DOI: 10.1128/aac.05404-11] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The objective of this study was to investigate photodynamic therapy (PDT), using blue dye and red light, for prophylaxis and treatment of cutaneous Candida albicans infections in mice. A mouse model of skin abrasion infected with C. albicans was developed by inoculating wounds measuring 1.2 cm by 1.2 cm with 10(6) or 10(7) CFU. The use of a luciferase-expressing strain of C. albicans allowed real-time monitoring of the extent of infection in mice noninvasively through bioluminescence imaging. The phenothiazinium salts toluidine blue O (TBO), methylene blue (MB), and new methylene blue (NMB) were compared as photosensitizers (PS) for the photodynamic inactivation of C. albicans in vitro. PDT in vivo was initiated either at 30 min or at 24 h after fungal inoculation to investigate the efficacies of PDT for both prophylaxis and treatment of infections. Light at 635 ± 15 nm or 660 ± 15 nm was delivered with a light dose of 78 J/cm(2) (for PDT at 30 min postinfection) or 120 J/cm(2) (for PDT at 24 h postinfection) in multiple exposures with bioluminescence imaging taking place after each exposure of light. In vitro studies showed that NMB was superior to TBO and MB as the PS in the photodynamic inactivation of C. albicans. The efficacy of PDT was related to the ratio of PS concentration to fungal cell density. PDT in vivo initiated either at 30 min or at 24 h postinfection significantly reduced C. albicans burden in the infected mouse skin abrasion wounds. These data suggest that PDT is a viable approach for prophylaxis and treatment of cutaneous C. albicans infections.
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