Liu Shuyuan, Yue Longtao, Gu Wenrui, Li Xiuyun, Zhang Liuping, Sun Shujuan
School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, Shandong Province, People's Republic of China.
Department of Pharmacy, Ordos Central Hospital, Ordos, 017000, Inner Mongolia, People's Republic of China.
PLoS One. 2016 Mar 17;11(3):e0150859. doi: 10.1371/journal.pone.0150859. eCollection 2016.
Candidiasis has increased significantly recently that threatens patients with low immunity. However, the number of antifungal drugs on the market is limited in comparison to the number of available antibacterial drugs. This fact, coupled with the increased frequency of fungal resistance, makes it necessary to develop new therapeutic strategies. Combination drug therapy is one of the most widely used and effective strategy to alleviate this problem. In this paper, we were aimed to evaluate the combined antifungal effects of four CCBs (calcium channel blockers), amlodipine (AML), nifedipine (NIF), benidipine (BEN) and flunarizine (FNZ) with fluconazole against C. albicans by checkerboard and time-killing method. In addition, we determined gene (CCH1, MID1, CNA1, CNB1, YVC1, CDR1, CDR2 and MDR1) expression by quantitative PCR and investigated the efflux pump activity of resistant candida albicans by rhodamine 6G assay to reveal the potential mechanisms. Finally, we concluded that there was a synergy when fluconazole combined with the four tested CCBs against resistant strains, with fractional inhibitory concentration index (FICI) <0.5, but no interaction against sensitive strains (FICI = 0.56 ~ 2). The mechanism studies revealed that fluconazole plus amlodipine caused down-regulating of CNA1, CNB1 (encoding calcineurin) and YVC1 (encoding calcium channel protein in vacuole membrane).
念珠菌病近来显著增加，威胁着免疫力低下的患者。然而，与现有的抗菌药物数量相比，市场上的抗真菌药物数量有限。这一事实，再加上真菌耐药性频率的增加，使得有必要开发新的治疗策略。联合药物治疗是缓解这一问题最广泛使用且有效的策略之一。在本文中，我们旨在通过棋盘法和时间杀菌法评估四种钙通道阻滞剂（CCB），氨氯地平（AML）、硝苯地平（NIF）、贝尼地平（BEN）和氟桂利嗪（FNZ）与氟康唑联合对白念珠菌的抗真菌效果。此外，我们通过定量PCR测定基因（CCH1、MID1、CNA1、CNB1、YVC1、CDR1、CDR2和MDR1）表达，并通过罗丹明6G测定法研究耐药白念珠菌的外排泵活性，以揭示潜在机制。最后，我们得出结论，氟康唑与四种受试CCB联合对抗耐药菌株时存在协同作用，部分抑菌浓度指数（FICI）<0.5，但对敏感菌株无相互作用（FICI = 0.56 ~ 2）。机制研究表明，氟康唑加氨氯地平导致编码钙调神经磷酸酶的CNA1、CNB1和编码液泡膜钙通道蛋白的YVC1下调。
