Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary.
Department of Conservative Dentistry, Semmelweis University, H-1088 Budapest, Hungary.
Int J Mol Sci. 2020 Nov 16;21(22):8614. doi: 10.3390/ijms21228614.
Cystic fibrosis (CF) is a hereditary disease caused by mutations in the gene encoding an epithelial anion channel. In CF, Cl and HCO hyposecretion, together with mucin hypersecretion, leads to airway dehydration and production of viscous mucus. This habitat is ideal for colonization by pathogenic bacteria. We have recently demonstrated that HCO inhibits the growth and biofilm formation of and when tested in laboratory culture media. Using the same bacteria our aim was to investigate the effects of HCO in artificial sputum medium (ASM), whose composition resembles CF mucus. Control ASM containing no NaHCO was incubated in ambient air (pH 7.4 or 8.0). ASM containing NaHCO (25 and 100 mM) was incubated in 5% CO (pH 7.4 and 8.0, respectively). Viable and cells were counted by colony-forming unit assay and flow cytometry after 6 h and 17 h of incubation. Biofilm formation was assessed after 48 h. The data show that HCO significantly decreased viable cell counts and biofilm formation in a concentration-dependent manner. These effects were due neither to extracellular alkalinization nor to altered osmolarity. These results show that HCO exerts direct antibacterial and antibiofilm effects on prevalent CF bacteria.
囊性纤维化（CF）是一种遗传性疾病，由编码上皮阴离子通道的基因突变引起。在 CF 中，Cl 和 HCO 的分泌不足，加上黏液分泌过多，导致气道脱水和产生粘性黏液。这种栖息地非常适合致病细菌的定植。我们最近证明，HCO 在实验室培养介质中抑制 和 的生长和生物膜形成。使用相同的细菌，我们的目的是研究 HCO 在人工痰培养基（ASM）中的作用，ASM 的成分类似于 CF 黏液。不含 NaHCO 的对照 ASM 在环境空气中（pH7.4 或 8.0）孵育。含有 NaHCO（25 和 100 mM）的 ASM 在 5%CO 中孵育（分别为 pH7.4 和 8.0）。孵育 6 小时和 17 小时后，通过集落形成单位测定和流式细胞术计数活的 和 细胞。孵育 48 小时后评估生物膜形成。数据显示，HCO 以浓度依赖性方式显著降低活细胞计数和生物膜形成。这些作用既不是由于细胞外碱化，也不是由于渗透压改变所致。这些结果表明，HCO 对常见的 CF 细菌具有直接的抗菌和抗生物膜作用。
