Integrated Research Center, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil.
Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil.
Oral Dis. 2020 Nov;26(8):1810-1819. doi: 10.1111/odi.13507. Epub 2020 Jul 29.
Oral candidiasis is the most common opportunistic fungal infection of oral mucosa and results from an overgrowth of Candida, especially Candida albicans. The potential anti-C. albicans and cytotoxicity of punicalagin (PCG), isolated from Punica granatum, alone or with nystatin (NYS) were evaluated.
Activity of compounds alone or in combinations was determined against two C. albicans strains (ATCC 90028 and SC5314). Minimal inhibitory concentration (MIC)-50 and Minimum Fungicidal Concentration (MFC) were assessed by XTT assay and CFU counts, respectively. For combinations, determination of fractional inhibitory concentration index was performed. Ergosterol pathway was investigated as a possible PCG antifungal mechanism. Cytotoxicity assays were undertaken on human primary oral keratinocytes and gingival fibroblasts incubated with antifungal concentrations of PCG and/or NYS for 24 hr.
Combination of NYS and PCG increased antifungal efficacy, compared with compounds tested alone. Combinations 4 (PCG-6.25 μg/ml; NYS-3.9 μg/ml) and 5 (PCG-12.5 μg/ml; NYS-1.95 μg/ml) were more effective since they reduced the MIC-50 of PCG (50 μg/ml) by 8 and 4 times, respectively, increased the candidal inhibition and nullified the PCG cytotoxicity for keratinocytes. PCG antifungal mechanism did not involve ergosterol biosynthesis pathway.
The favorable outcomes for combination of PCG and NYS encourage further testing this therapeutic strategy against C. albicans.
口腔念珠菌病是口腔黏膜最常见的机会性真菌感染，是由念珠菌过度生长引起的，尤其是白色念珠菌。本研究评估了从石榴（Punica granatum）中分离得到的鞣花单宁（PCG）单独或与制霉菌素（NYS）联合使用时的抗白念珠菌活性和细胞毒性。
单独或联合使用化合物对两种白念珠菌菌株（ATCC 90028 和 SC5314）进行活性测定。采用 XTT 法和 CFU 计数法分别评估最小抑菌浓度（MIC）-50 和最低杀菌浓度（MFC）。对于联合用药，采用部分抑菌浓度指数（FICI）来确定。研究了 PCG 的抗真菌机制是否与麦角固醇途径有关。用人原代口腔角质形成细胞和牙龈成纤维细胞进行细胞毒性试验，用 PCG 和/或 NYS 的抗真菌浓度孵育 24 小时。
与单独使用化合物相比，NYS 与 PCG 的联合使用增加了抗真菌效果。组合 4（PCG-6.25μg/ml；NYS-3.9μg/ml）和 5（PCG-12.5μg/ml；NYS-1.95μg/ml）更有效，因为它们将 PCG 的 MIC-50（50μg/ml）分别降低了 8 倍和 4 倍，增加了对白色念珠菌的抑制作用，并消除了 PCG 对角质形成细胞的细胞毒性。PCG 的抗真菌机制不涉及麦角固醇生物合成途径。
PCG 与 NYS 联合应用的良好结果鼓励进一步研究这种治疗策略对白念珠菌的疗效。
