Antibiofilm and antifungal activities of medium-chain fatty acids against Candida albicans via mimicking of the quorum-sensing molecule farnesol

The Role of Fatty Acid Metabolites in Vaginal Health and Disease: Application to Candidiasis

Although the vast majority of women encounters at least one vaginal infection during their life, the amount of microbiome-related research performed in this area lags behind compared to alternative niches such as the intestinal tract. As a result, effective means of diagnosis and treatment, especially of recurrent infections, are limited. The role of the metabolome in vaginal health is largely elusive. It has been shown that lactate produced by the numerous lactobacilli present promotes health by limiting the chance of infection. Short chain fatty acids (SCFA) have been mainly linked to dysbiosis, although the causality of this relationship is still under debate. In this review, we aim to bring together information on the role of the vaginal metabolome and microbiome in infections caused by Candida. Vulvovaginal candidiasis affects near to 70% of all women at least once in their life with a significant proportion of women suffering from the recurrent variant. We assess the role of fatty acid metabolites, mainly SCFA and lactate, in onset of infection and virulence of the fungal pathogen. In addition, we pinpoint where lack of research limits our understanding of the molecular processes involved and restricts the possibility of developing novel treatment strategies.

The paradoxical and still obscure properties of fungal extracellular vesicles

Early compositional studies of fungal EVs revealed a complex combination of biomolecules, including proteins, lipids, glycans, polysaccharides, nucleic acid and pigments, indicating that these compartments could be involved with multiple functions. Curiously, some of the activities attributed to fungal EVs were already attested experimentally and are implicated with contrasting effects in vitro and in vivo. For instance, the presence of virulence factors is correlated with increased pathogenic potential. Indeed, the administration to hosts of EVs along with some fungal pathogens seems to help the disease development. However, it has been clearly shown that immunization of insects and mice with fungal EVs can protect these animals against a subsequent infection. Fungal EVs not only influence the host response, as concluded from the observation that these compartments also work as messengers between fungal organisms. In this context, despite their size characterization, other physical properties of EVs are poorly known. For instance, their stability and half-life under physiological conditions can be a crucial parameter determining their long-distance effects. In this review, we will discuss the paradoxical and still unexploited functions and properties of fungal EVs that could be determinant for their biological functions.

Reassessing the Use of Undecanoic Acid as a Therapeutic Strategy for Treating Fungal Infections

Treating fungal infections is challenging and frequently requires long-term courses of antifungal drugs. Considering the limited number of existing antifungal drugs, it is crucial to evaluate the possibility of repositioning drugs with antifungal properties and to revisit older antifungals for applications in combined therapy, which could widen the range of therapeutic possibilities. Undecanoic acid is a saturated medium-chain fatty acid with known antifungal effects; however, its antifungal properties have not been extensively explored. Recent advances indicate that the toxic effect of undecanoic acid involves modulation of fungal metabolism through its effects on the expression of fungal genes that are critical for virulence. Additionally, undecanoic acid is suitable for chemical modification and might be useful in synergic therapies. This review highlights the use of undecanoic acid in antifungal treatments, reinforcing its known activity against dermatophytes. Specifically, in Trichophyton rubrum, against which the activity of undecanoic acid has been most widely studied, undecanoic acid elicits profound effects on pivotal processes in the cell wall, membrane assembly, lipid metabolism, pathogenesis, and even mRNA processing. Considering the known antifungal activities and associated mechanisms of undecanoic acid, its potential use in combination therapy, and the ability to modify the parent compound structure, undecanoic acid shows promise as a novel therapeutic against fungal infections.