Instituto de Pesquisa & Desenvolvimento - IP&D, Universidade do Vale do Paraíba - UNIVAP. Av. Shishima Hifumi 2911, CEP: 12, São José dos Campos 244-000, Brazil.
Instituto de Pesquisa & Desenvolvimento - IP&D, Universidade do Vale do Paraíba - UNIVAP. Av. Shishima Hifumi 2911, CEP: 12, São José dos Campos 244-000, Brazil.
Photodiagnosis Photodyn Ther. 2023 Jun;42:103600. doi: 10.1016/j.pdpdt.2023.103600. Epub 2023 May 6.
Although Candida albicans is the most frequent etiological agent of candidiasis, it has been reported a sizable number of infections related to the non-albicans Candida (NAC) species, Candida krusei. In addition, dual biofilms (biofilms composed by two species) may easily occur in vivo, becoming even more challenging the treatment of an infection. The fungicide effect of Photodynamic Therapy (PDT), using toluidine blue O (TBO) on both C. albicans and C. krusei development has been demonstrated. Thus, the objective of this study was to investigate the effects of PDT on dual-species biofilms of Candida albicans and Candida krusei.
The effect of PDT was observed on the metabolic activity of mature dual-species biofilms of Candida albicans and Candida krusei by a metabolic assay based on the reduction of XTT (2,3-bis(2‑methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide sodium salt) assay and the identification of Candida albicans and Candida krusei was performed on CHROMagar Candida medium.
it was observed a reduction of ∼30% in the metabolic activity of a mature biofilm treated with PDT, using 0.05 mg·mL TBO and during biofilm formation a predominance of C. albicans on C. krusei was observed. The inhibition observed was related to reduction in the number of Colony Forming Units (CFU) of Candida albicans from 31.33 ± 3.7 to 17.0 ± 1.5. The number of CFU of C. krusei was not significantly modified.
These results demonstrated the efficiency of PDT in inhibiting the dual-species biofilms of Candida albicans and Candida krusei by reducing C. albicans development.
虽然白色念珠菌是念珠菌病最常见的病因，但已报道大量与非白色念珠菌（NAC）物种，即克柔念珠菌有关的感染。此外，双生物膜（由两种物种组成的生物膜）在体内很容易发生，这使得感染的治疗更加具有挑战性。光动力疗法（PDT）使用甲苯胺蓝 O（TBO）对白色念珠菌和克柔念珠菌的生长的杀菌作用已经得到证实。因此，本研究的目的是研究 PDT 对白色念珠菌和克柔念珠菌双物种生物膜的影响。
通过基于 XTT（2,3-双（2-甲氧基-4-硝基-5-磺苯基）-2H-四唑-5-羧基苯胺钠盐）还原的代谢测定法观察 PDT 对成熟的白色念珠菌和克柔念珠菌双物种生物膜代谢活性的影响，并在 CHROMagar Candida 培养基上鉴定白色念珠菌和克柔念珠菌。
使用 0.05 mg·mL TBO 进行 PDT 处理后，成熟生物膜的代谢活性降低了约 30%，并且在生物膜形成过程中观察到白色念珠菌对克柔念珠菌的优势。观察到的抑制作用与白色念珠菌的菌落形成单位（CFU）数量减少有关，从 31.33±3.7 减少到 17.0±1.5。克柔念珠菌的 CFU 数量没有明显改变。
这些结果表明 PDT 通过减少白色念珠菌的生长有效抑制白色念珠菌和克柔念珠菌的双物种生物膜。
