Zangirolami Amanda C, Yerra Koteswara Rao, Yakovlev Vladislav V, Blanco Kate C, Bagnato Vanderlei S
Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA.
São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, São Paulo, Brazil.
Antibiotics (Basel). 2024 Nov 21;13(12):1111. doi: 10.3390/antibiotics13121111.
Antibiotics remain the most effective option for combating infections. However, the situation has shifted from ideal to concerning, as bacterial resistance to antibiotics is increasing in both prevalence and strength. : This study explores the synergistic/antagonistic potential of combining antibiotic and photodynamic therapy (PDT) against . : We conducted in vitro experiments to observe the effect of the sequential application of antibiotics and photodynamic therapy with a time interval between them. The antibiotics used were ciprofloxacin, ceftriaxone, and gentamicin, and Photodithazine was employed as the photosensitizer, with the PDT performed at different light doses of 660 nm radiation. : The combined effect was highly dependent on the antibiotic. While for gentamicin, the combination of antibiotic and PDT treatment was always synergistic, for ciprofloxacin, it could be severely antagonistic. Each antibiotic exhibited a distinctive pattern of interaction with PDT. Gentamicin resulted in the largest enhancement in bactericidal activity combined with PDT, requiring lower antibiotic concentrations to achieve significant bacterial reduction. Ceftriaxone's bactericidal action was less influenced by PDT intensity, maintaining a stable efficacy regardless of different PDT dosages. Conversely, the outcome of ciprofloxacin was highly dependent on the antibiotic concentration changing from synergic to antagonistic action. : The findings advocate for the development of treatment protocols that combine antibiotics and PDT and necessitate the establishment of the criterion for the dosage and periodicity of administration of such combination protocols. The demonstrated results open the doors wide to new applications and opportunities to combat infectious diseases through the combined use of photodynamic therapy and antibiotics.
抗生素仍然是对抗感染最有效的选择。然而，情况已从理想转变为令人担忧，因为细菌对抗生素的耐药性在发生率和强度上都在增加。本研究探讨了联合使用抗生素和光动力疗法（PDT）对抗[具体对象未提及]的协同/拮抗潜力。我们进行了体外实验，以观察抗生素和光动力疗法序贯应用且两者之间有时间间隔时的效果。使用的抗生素为环丙沙星、头孢曲松和庆大霉素，光二噻嗪用作光敏剂，光动力疗法在660nm不同光剂量下进行。联合效果高度依赖于抗生素。对于庆大霉素，抗生素与光动力疗法联合治疗始终具有协同作用，而对于环丙沙星，可能具有严重的拮抗作用。每种抗生素与光动力疗法都表现出独特的相互作用模式。庆大霉素与光动力疗法联合时杀菌活性增强最大，实现显著细菌减少所需的抗生素浓度较低。头孢曲松的杀菌作用受光动力疗法强度影响较小，无论光动力疗法剂量如何，疗效都保持稳定。相反，环丙沙星的结果高度依赖于抗生素浓度，其作用从协同变为拮抗。这些发现提倡开发联合抗生素和光动力疗法的治疗方案，并且有必要建立此类联合方案给药剂量和周期的标准。所展示的结果为通过联合使用光动力疗法和抗生素对抗传染病开辟了新的应用和机会。
