Dos Santos Jéssica Diane, de Alvarenga Janaína Araújo, Rossoni Rodnei Dennis, García Maíra Terra, Moraes Renata Mendonça, Anbinder Ana Lia, Cardoso Jorge Antonio Olavo, Junqueira Juliana Campos
Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, UNESP - Univ. Estadual Paulista, São José dos Campos, SP, Brazil.
Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, UNESP - Univ. Estadual Paulista, São José dos Campos, SP, Brazil.
Microb Pathog. 2017 Sep;110:507-511. doi: 10.1016/j.micpath.2017.07.045. Epub 2017 Jul 28.
Porphyromonas gingivalis is an important pathogen in the development of periodontal disease. Our study investigated if the treatment with antimicrobial photodynamic therapy (aPDT) that employs a nontoxic dye, followed by irradiation with harmless visible light can attenuate the experimental infection of P. gingivalis in Galleria mellonella. Firstly, different concentrations of P. gingivalis ranging from 10 to 10 cells/larva were injected into the animal to obtain a lethal concentration. Next, the following groups of G. mellonella infected with P. gingivalis were evaluated: inoculation of the photosensitizer and application of laser (P + L+), inoculation of physiologic solution and application of laser (P-L+), inoculation the photosensitizer without laser (P + L-) and inoculation of physiologic solution without Laser (P-L-). The effects of aPDT on infection by P. gingivalis were evaluated by survival curve analysis and hemocytes count. A lethal concentration of 10 cells/larva was adopted for evaluating the effects of aPDT on experimental infection with P. gingivalis. We found that after 120 s of PDT application, the death of G. mellonella was significantly lower compared to the control groups (p = 0.0010). Moreover, the hemocyte density in the P+L+ group was increased by 9.6 × 10 cells/mL (2.62-fold increase) compared to the infected larvae with no treatment (L-P- group) (p = 0.0175). Finally, we verified that the aPDT led to a significant reduction of the number of P. gingivalis cells in G. mellonella hemolymph. In conclusion, PDT application was effective against P. gingivalis infection by increasing the survival of G. mellonella and was able to increase the circulating hemocytes indicating that PDT activates the G. mellonella immune system.
牙龈卟啉单胞菌是牙周疾病发展过程中的一种重要病原体。我们的研究调查了采用无毒染料的抗菌光动力疗法（aPDT），随后用无害可见光进行照射，是否能够减轻蜡螟幼虫体内牙龈卟啉单胞菌的实验性感染。首先，将不同浓度（范围为10⁴至10⁷个细胞/幼虫）的牙龈卟啉单胞菌注射到动物体内以获得致死浓度。接下来，对以下感染牙龈卟啉单胞菌的蜡螟幼虫组进行评估：接种光敏剂并应用激光（P + L +）、接种生理溶液并应用激光（P - L +）、接种光敏剂但不应用激光（P + L -）以及接种生理溶液且不应用激光（P - L -）。通过生存曲线分析和血细胞计数评估aPDT对牙龈卟啉单胞菌感染的影响。采用10⁷个细胞/幼虫的致死浓度来评估aPDT对牙龈卟啉单胞菌实验性感染的影响。我们发现，在应用光动力疗法120秒后，与对照组相比，蜡螟幼虫的死亡率显著降低（p = 0.0010）。此外，与未处理的感染幼虫（L - P -组）相比，P + L +组的血细胞密度增加了9.6×10⁶个细胞/毫升（增加了2.62倍）（p = 0.0175）。最后，我们证实aPDT导致蜡螟血淋巴中牙龈卟啉单胞菌细胞数量显著减少。总之，应用光动力疗法通过提高蜡螟幼虫的存活率，对牙龈卟啉单胞菌感染有效，并且能够增加循环血细胞数量，表明光动力疗法激活了蜡螟的免疫系统。
