title: Novel Nystatin A₁ derivatives exhibiting low host cell toxicity and antifungal activity in an in vitro model of oral candidosis.
abstract: Opportunistic oral infections caused by Candida albicans are frequent problems in immunocompromised patients. Management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. Given these issues, our investigations have focused on novel derivatives of the antifungal antibiotic Nystatin A1, generated by modifications at the amino group of this molecule. The aims of this study were to evaluate the antifungal effectiveness and host cell toxicity of these new compounds using an in vitro model of oral candidosis based on a reconstituted human oral epithelium (RHOE). Initial studies employing broth microdilution, revealed that against planktonic C. albicans, Nystatin A1 had lower minimal inhibitory concentration than novel derivatives. However, Nystatin A1 was also markedly more toxic against human keratinocyte cells. Interestingly, using live/dead staining to assess C. albicans and tissue cell viability after RHOE infection, Nystatin A1 derivatives were more active against Candida with lower toxicity to epithelial cells than the parent drug. Lactate dehydrogenase activity released by the RHOE indicated a fourfold reduction in tissue damage when certain Nystatin derivatives were used compared with Nystatin A1. Furthermore, compared with Nystatin A1, colonisation of the oral epithelium by C. albicans was notably reduced by the new polyenes. In the absence of antifungal agents, confocal laser scanning microscopy showed that C. albicans extensively invaded the RHOE. However, the presence of the novel derivatives greatly reduced or totally prevented this fungal invasion.
authors.affiliation: Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology (GUT), 11/12 Narutowicza Street, 80-233, Gdańsk, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Boros-Majewska
authors.forename: Natalia
authors.initials: N
authors.lastname: Salewska
authors.forename: Edward
authors.initials: E
authors.lastname: Borowski
authors.forename: Sławomir
authors.initials: S
authors.lastname: Milewski
authors.forename: Sladjana
authors.initials: S
authors.lastname: Malic
authors.forename: Xiao-Qing
authors.initials: XQ
authors.lastname: Wei
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Hayes
authors.forename: Melanie J
authors.initials: MJ
authors.lastname: Wilson
authors.forename: David W
authors.initials: DW
authors.lastname: Williams
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D002176:Candida albicans / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004848:Epithelium / Q000382:microbiology; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D009761:Nystatin / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D009924:Organ Culture Techniques
chemical_list: D000935:Antifungal Agents; D009761:Nystatin