Antimicrobial photodynamic therapy with methylene blue and its derivatives in animal studies: Systematic review
Ana Paula Martin Cardozo1, Daniela de Fátima Teixeira da Silva1, Kristianne Porta Santos Fernandes1
1Postgraduate Program in Biophotonics-Medicine Universidade Nove de Julho, Universidade Nove de Julho, São Paulo, Brazil.
Background:
Infections are complications in the wound healing process, and their treatment can lead to antibiotic overuse and bacterial resistance. Antimicrobial photodynamic therapy (aPDT) is used to treat infectious diseases caused by fungi, viruses, or bacteria. Methylene blue (MB) and its derivatives are commonly used dyes in antimicrobial photodynamic therapy (aPDT-MB).
Methods:
This study is a PRISMA systematic review of animal models used to discuss the usefulness and therapeutic parameters of aPDT-MB or its derivatives for treating infected skin wounds.
Results:
After an extensive literature review, 13 controlled trials totaling 261 animals were selected to evaluate skin infection by leishmaniasis and cutaneous bacterial and fungal infections. All studies found results favoring the use of aPDT-MB. Great variability in parameters was found for radiant exposure from 12 to 360 J/cm2, MB diluted in saline solution or distilled water, irradiation time from 40 to 3600 s, irradiance most commonly at a maximum of 100 mW/cm2, and wavelength used mainly in the 630-670 nm range.
Conclusion:
MB is a safe and promising agent used as a photosensitizer in aPDT for skin-infected lesions. There is great variability in the parameters found. Comparisons concerning concentration, irradiation time, and light intensity need to be performed.
Insights
Antimicrobial photodynamic therapy using methylene blue (MB) shows promise for treating skin infections in animal models. Further research is needed to optimize treatment parameters for this effective therapy.
Area of Science:
- Wound healing and infectious disease treatment.
- Photodynamic therapy and photochemistry.
Background:
- Infections impede wound healing, leading to antibiotic resistance.
- Antimicrobial photodynamic therapy (aPDT) offers an alternative for treating microbial infections.
- Methylene blue (MB) and its derivatives are key photosensitizers in aPDT.
Purpose of the Study:
- To systematically review animal models evaluating the efficacy of aPDT with MB (aPDT-MB).
- To identify optimal therapeutic parameters for aPDT-MB in treating infected skin wounds.
Main Methods:
- A PRISMA systematic review of controlled animal trials.
- Literature search for studies on aPDT-MB for skin infections.
Main Results:
- 13 trials with 261 animals were included, focusing on leishmaniasis and bacterial/fungal skin infections.
- All studies demonstrated favorable outcomes for aPDT-MB treatment.
- Significant variability observed in radiant exposure (12-360 J/cm²), MB dilution, irradiation time (40-3600 s), irradiance (≤100 mW/cm²), and wavelength (630-670 nm).
Conclusions:
- Methylene blue is a safe photosensitizer for aPDT in skin infections.
- aPDT-MB is a promising therapeutic approach for infected skin lesions.
- Further studies are required to standardize treatment parameters like concentration, irradiation time, and light intensity.
