Department of Physiology and Pathology, School of Dentistry, São Paulo State University (Unesp), Rua Humaitá, 1680, Araraquara, SP 14801-903, Brazil; Department of Oral Diagnosis and Surgery, School of Dentistry, São Paulo State University (Unesp), Rua Humaitá, 1680, Araraquara, SP 14801-903, Brazil.
Department of Physiology and Pathology, School of Dentistry, São Paulo State University (Unesp), Rua Humaitá, 1680, Araraquara, SP 14801-903, Brazil.
Photodiagnosis Photodyn Ther. 2023 Jun;42:103322. doi: 10.1016/j.pdpdt.2023.103322. Epub 2023 Feb 10.
New therapies involving natural products and nanobiotechnology open additional perspectives to reduce endodontic infections. Curcumin is a natural polyphenol extracted from the dry rhizome of curcuma long Linn with therapeutic properties for application in nanobiotechnology and as a photosensitizer for photodynamic therapy. This study aimed to synthesize a novel polymeric nanoparticle of poly (lactic-co-glycolic acid) (PLGA) loaded with curcumin (NP+Cur), and evaluate its antimicrobial activity against endodontic biofilms. Additionally, its biocompatibility using oral keratinocytes was assessed. The polymeric NP+Cur was prepared by the nanoprecipitation method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were calculated for the three endodontic bacteria (Enterococcus faecalis, Streptococcus oralis and Actinomyces viscosus). Antibacterial activity of NP+Cur against single- and multispecies biofilm pre-formed on the botton 24-well plate and into dentin tubules of bovine teeth were evaluated by colony forming units and confocal laser scanning microscopy. The pre-irradiation time was 5 min followed by exposure to blue light-emitting diode at 450 nm for the photodynamic treatment. Cell viability using oral keratinocytes was assessed by Alamar Blue assay. MIC and MBC showed antibacterial activity of NP+Cur against endodontic bacteria. A treatment of pre-formed biofilms of endodontic bacteria with NP+Cur also significantly decreased bacterial viability. The concentration of 325 μg/mL of photoactivated NP+Cur was the one that most reduced the viability of the endodontic bacteria evaluated. Regarding biocompatibility, NP+Cur 325 μg/mL and pure nanoparticles showed a cell viability greater than 80%. The novel polymeric nanoparticles loaded with curcumin may be a promising adjunct use to treatment of endodontic infections.
新型疗法涉及天然产物和纳米生物技术，为减少根管感染提供了更多的可能性。姜黄素是一种天然多酚，从姜黄的干燥根茎中提取，具有治疗特性，可应用于纳米生物技术，并作为光动力疗法的光敏剂。本研究旨在合成负载姜黄素的新型聚乳酸-羟基乙酸共聚物（PLGA）纳米粒子（NP+Cur），并评估其对根管生物膜的抗菌活性。此外，还评估了其对口腔角质细胞的生物相容性。通过纳米沉淀法制备了聚合物 NP+Cur。计算了三种根管细菌（粪肠球菌、口腔链球菌和粘性放线菌）的最小抑菌浓度（MIC）和最小杀菌浓度（MBC）。通过平板菌落形成单位计数和共聚焦激光扫描显微镜评估 NP+Cur 对预先形成于平底 24 孔板和牛牙根管内的单种和多种生物膜的抗菌活性。光动力治疗前预照射时间为 5 分钟，然后用 450nm 蓝光发射二极管照射。采用 Alamar Blue 法评估口腔角质细胞的细胞活力。MIC 和 MBC 显示 NP+Cur 对根管细菌具有抗菌活性。用 NP+Cur 处理预先形成的根管细菌生物膜也显著降低了细菌的活力。评价的三种根管细菌中，浓度为 325μg/mL 的光激活 NP+Cur 使细菌活力降低最多。关于生物相容性，325μg/mL 的 NP+Cur 和纯纳米粒子的细胞活力大于 80%。负载姜黄素的新型聚合物纳米粒子可能是治疗根管感染的一种有前途的辅助治疗方法。
