Latief Miftahul Akhyar, Chikama Taiichiro, Shibasaki Momoko, Sasaki Takaaki, Ko Ji-Ae, Kiuchi Yoshiaki, Sakaguchi Takemasa, Obana Akira
Department of Ophthalmology and Visual Science, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-Ku, Hiroshima, 734-8551, Japan.
Lasers Med Sci. 2015 Jan;30(1):383-7. doi: 10.1007/s10103-014-1681-6. Epub 2014 Oct 30.
Efforts to identify improved treatments for corneal infection include the development of photodynamic antimicrobial chemotherapy (PACT). We evaluated the antimicrobial effect of PACT with a novel porphyrin derivative, TONS 504, and a novel light system on methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA). Bacteria were irradiated with a light-emitting diode (LED) at energies of 10, 20, or 30 J/cm(2) in the presence of various concentrations of TONS 504. Bacterial viability was assessed at 30 min and 24 h after irradiation by determination of colony formation on agar plates. PACT inhibited the growth of both MSSA and MRSA as early as 30 min after light exposure. Complete inhibition of bacterial growth was apparent at 24 h after irradiation at a TONS 504 concentration of 1 mg/L and LED energies of ≥10 J/cm(2) or a TONS 504 concentration of 0.5 mg/L and LED energies of ≥20 J/cm(2) for MSSA, and at a TONS 504 concentration of 10 mg/L and LED energies of ≥10 J/cm(2) or of a TONS 504 concentration of 1 mg/L and LED energies of ≥20 J/cm(2) for MRSA. Bacterial growth was unaffected by TONS 504 in the absence of irradiation or by irradiation in the absence of TONS 504. Our results thus demonstrate the antimicrobial efficacy of PACT with TONS 504 and a LED against both MSSA and MRSA in vitro, and they therefore provide a basis for further investigation of this system as a potential treatment for corneal infection.
确定角膜感染更佳治疗方法的努力包括光动力抗菌化学疗法（PACT）的研发。我们评估了新型卟啉衍生物TONS 504和新型光照系统的光动力抗菌化学疗法对甲氧西林敏感金黄色葡萄球菌（MSSA）和耐甲氧西林金黄色葡萄球菌（MRSA）的抗菌效果。在不同浓度的TONS 504存在下，用能量为10、20或30 J/cm²的发光二极管（LED）照射细菌。通过测定琼脂平板上的菌落形成情况，在照射后30分钟和24小时评估细菌活力。光动力抗菌化学疗法在光照后30分钟就抑制了MSSA和MRSA的生长。对于MSSA，在照射后24小时，当TONS 504浓度为1 mg/L且LED能量≥10 J/cm²，或TONS 504浓度为0.5 mg/L且LED能量≥20 J/cm²时，细菌生长完全受到抑制；对于MRSA，在照射后24小时，当TONS 504浓度为10 mg/L且LED能量≥10 J/cm²，或TONS 504浓度为1 mg/L且LED能量≥20 J/cm²时，细菌生长完全受到抑制。在无照射情况下，TONS 504对细菌生长无影响；在无TONS 504情况下，照射对细菌生长也无影响。因此，我们的结果证明了TONS 504和LED的光动力抗菌化学疗法在体外对MSSA和MRSA均具有抗菌效果，从而为进一步研究该系统作为角膜感染的潜在治疗方法提供了依据。
