Laboratório de Glicobiología de Eucariotos (LaGE), Depto. Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, 21941-590, Rio de Janeiro, Brazil.
Depto de Química, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900, Rio de Janeiro, Brazil.
Med Mycol. 2021 Oct 4;59(10):993-1005. doi: 10.1093/mmy/myab028.
Silver compounds are widely known for their antimicrobial activity, but can exert toxic effects to the host. Among the strategies to reduce its toxicity, incorporation into biopolymers has shown promising results. We investigated the green syntheses of silver nanoparticles (AgNPs) and their functionalization in a chitosan matrix (AgNPs@Chi) as a potential treatment against Candida spp. Inhibitory concentrations ranging between 0.06 and 1 μg/ml were observed against distinct Candida species. Nanocomposite-treated cells displayed cytoplasmic degeneration and a cell membrane and wall disruption. Silver nanocomposites in combination with fluconazole and amphotericin B showed an additive effect when analyzed by the Bliss method. The low cytotoxicity displayed in mammalian cells and in the Galleria mellonella larvae suggested their potential use in vivo. When tested as a topical treatment against murine cutaneous candidiasis, silver nanocomposites reduced the skin fungal burden in a dose-response behavior and favored tissue repair. In addition, the anti-biofilm effect of AgNPs@Chi in human nail model was demonstrated, suggesting that the polymeric formulation of AgNPs does not affect antifungal activity even against sessile cells. Our results suggest that AgNPs@Chi seems to be a less toxic and effective topical treatment for superficial candidiasis.
This study demonstrated the efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Candida. AgNPs incorporated in chitosan displayed a reduced toxicity. Tests in infected mice showed the effectiveness of the treatment. AgNPs-chitosan could be an alternative to combat candidiasis.
银化合物因其抗菌活性而广为人知，但也会对宿主产生毒性作用。在降低其毒性的策略中，将其掺入生物聚合物已显示出有希望的结果。我们研究了银纳米粒子（AgNPs）的绿色合成及其在壳聚糖基质中的功能化，作为治疗念珠菌属的潜在方法。针对不同的念珠菌属物种，观察到的抑制浓度在 0.06 至 1μg/ml 之间。经纳米复合材料处理的细胞显示细胞质变性、细胞膜和细胞壁破裂。通过 Bliss 法分析，银纳米复合材料与氟康唑和两性霉素 B 联合使用显示出相加作用。哺乳动物细胞和大蜡螟幼虫中显示出的低细胞毒性表明它们在体内具有潜在的用途。当作为局部治疗方法用于治疗小鼠皮肤念珠菌病时，银纳米复合材料以剂量反应的方式减少皮肤真菌负担，并促进组织修复。此外，还在人指甲模型中证明了 AgNPs@Chi 的抗生物膜作用，表明即使针对静止细胞，AgNPs 的聚合物配方也不会影响抗真菌活性。我们的研究结果表明，AgNPs@Chi 似乎是一种毒性更低且有效的治疗浅表念珠菌病的局部治疗方法。
本研究证明了银纳米粒子（AgNPs）抑制念珠菌生长的功效。掺入壳聚糖的 AgNPs 显示出降低的毒性。感染小鼠的测试表明了该治疗方法的有效性。AgNPs-壳聚糖可能是对抗念珠菌病的一种替代方法。
