Inhibition of hyphae formation andSIR2expression inCandida albicanstreated with freshAllium sativum(garlic) extract

Abstract

Aims: The aims of the present study were to determine whether Allium sativum (garlic) extract has any effect on the morphology transformation of Candida albicans, and to investigate whether it could alter the gene expression level of SIR2, a morphogenetic control gene and SAP4, a gene encoding secreted aspartyl proteinase. Methods and Results: Candida albicans cells were incubated with a range of concentrations of fresh garlic extract, and the morphology was monitored via light microscopy. Garlic extract treatment caused the transition of yeast form to hyphal form to be obviated. The expression of SIR2 was down‐regulated from 1·2‐ to 2·5‐fold with increasing concentration of the garlic extract, as determined from relative quantitative reverse transcription‐polymerase chain reaction. There was no difference in the SAP4 expression in control vs treated cultures. Conclusions: Garlic and its bioactive components have the ability to suppress hyphae production and to affect the expression level of SIR2 gene. Significance and Impact of the Study: Hyphal production is an essential virulence determinant of C. albicans for invasive infections, therefore garlic and its constituents can be effective not only against colonizing C. albicans strains present in mucosal infections, but also virulent strains causing systemic or invasive candidiasis.

2‐dodecanol (decyl methyl carbinol) inhibits hyphal formation and SIR2 expression in C. albicans

“…Our study found that there is a positive correlation between SIR2 expression and true hyphae development. Recently garlic was also shown to be able to suppress hyphae production and also SIR2 expression was shown to be downregulated with increasing concentrations of garlic extract [4].…”

“…Therefore the inhibition of filamentation may reduce the pathogenesis of systemic candidiasis. CaSIR2 appears to play a role in phenotypic switching [3], and its expression was recently shown to be suppressed by fresh garlic treatment [4]. Dodecanol has been shown by Hogan et al [5] to be similar to farnesol, a C. albicans quorum-sensing molecule (QSMs), in its ability to inhibit yeast-hyphae transition.…”

Garlic extract and its selected organosulphur constituents promote ileal immune responses ex vivo

“…Indeed, garlic and some bioactive derivatives reportedly showed antifungal activities in vitro (Low et al, 2008). Hence, the mechanisms of antifungal activity by garlic might be due to direct action against fungi as well as potentiating mucosal immune responses by …”

Interspecies Interactions between Clostridium difficile and Candida albicans

“…Other signaling compounds (e.g., farnesol [reviewed in reference 62]) and antifungals (e.g., fluconazole [63]) are also toxic at higher levels. Hyphal inhibitors are already being used to treat candidiasis (64, 65), and our finding may lead to enhanced treatment options for C. albicans infections. The mode of action of p -cresol toward C. albicans is unknown.…”