Anti-dermatophytic activity of cold atmospheric plasma against Trichophyton rubrum via affecting fungal growth, morphology, drug susceptibility and HSP90 gene expression

Abstract

Trichophyton rubrum, a major human pathogenic dermatophyte, is responsible for the most recurrent dermatophytoses as globally important superficial fungal infections. Typical chemotherapy is used to handle such infections; however, emerging drug resistance and side effects necessitate the new remedial method development. Cold atmospheric plasma (CAP) is an emerging technology, consisted of neutral and charged particles and photons newly developed as a potent and safe antimicrobial technique to combat drug-resistant microbial pathogens. In the present study, the vast effects of CAP irradiation containing oxygen (2%) and helium (98%) on T. rubrum growth and pathogenicity were explored. After exposure of T. rubrum to CAP jet for 90, 120, 150, 180, and 210 s in 96-well microtiter plates, cell morphology and viability, ergosterol content of fungal hyphae, HSP90 gene expression, and the pattern of drug susceptibility were studied by using electron microscopy, RT-qPCR, spectrophotometry, disk diffusion and CLSI microbroth dilution methods. CAP irradiation significantly inhibited the fungal growth by 25.83 to 89.10%, reduced fungal cell viability by 11.68 to 87.71%, disrupted cellular membranous organelles and structures of the fungal hyphae, and suppressed efficiently the expression of HSP90 gene by 2 folds in 210 s exposure. Taken together, our results demonstrated that CAP is an efficient tool with potential in-vivo therapeutic applications against chronic dermatophytosis caused by T. rubrum due to its effectiveness, harmless, and ease of access.

Cold atmospheric plasma therapy for Malassezia folliculitis: Laboratory investigations and a randomized clinical trial

“…reported similar CAP‐induced cell wall damage in T. rubrum under scanning electron microscopy. 17 Traditionally, studies evaluating the effect of CAP in Malassezia genus have focused on planktonic cells in pure culture despite the fact that most microbes exist as organized biofilm communities of cells in natural ecosystems. The biofilm structure enhances the inherent resistance of microbes to both physical and chemical stressors and mediates the regulation of community‐driven gene expression.…”

“…In line with our results, Safi-Samghabadi et al reported similar CAP-induced cell wall damage in T. rubrum under scanning electron microscopy. 17 Traditionally, studies evaluating the effect of CAP in Malassezia genus have focused on planktonic cells in pure culture despite the fact that most microbes exist as organized biofilm communities of cells in natural ecosystems.…”