Thymol has antifungal activity against Candida albicans during infection and maintains the innate immune response required for function of the p38 MAPK signaling pathway in Caenorhabditis elegans

Abstract

The Caenorhabditis elegans model can be used to study Candida albicans virulence and host immunity, as well as to identify plant-derived natural products to use against C. albicans. Thymol is a hydrophobic phenol compound from the aromatic plant thyme. In this study, the in vitro data demonstrated concentration-dependent thymol inhibition of both C. albicans growth and biofilm formation during different developmental phases. With the aid of the C. elegans system, we performed in vivo assays, and our results further showed the ability of thymol to increase C. elegans life span during infection, inhibit C. albicans colony formation in the C. elegans intestine, and increase the expression levels of host antimicrobial genes. Moreover, among the genes that encode the p38 MAPK signaling pathway, mutation of the pmk-1 or sek-1 gene decreased the beneficial effects of thymol's antifungal activity against C. albicans and thymol's maintenance of the innate immune response in nematodes. Western blot data showed the level of phosphorylation of pmk-1 was dramatically decreased against C. albicans. In nematodes, treatment with thymol recovered the dysregulation of pmk-1 and sek-1 gene expressions, the phosphorylation level of PMK-1 caused by C. albicans infection. Therefore, thymol may act, at least in part, through the function of the p38 MAPK signaling pathway to protect against C. albicans infection and maintain the host innate immune response to C. albicans. Our results indicate that the p38 MAPK signaling pathway plays a crucial role in regulating the beneficial effects observed after nematodes infected with C. albicans were treated with thymol.

The clinical evaluation of Vi-one chlorhexidine mouthwash on plaque-induced gingivitis: A double-blind randomized clinical trial

“…Therefore, the differences between the results of the present study and other studies might be attributed to thymol in addition to CHX in the composition of Vi-one mouthwash and their possible synergistic effect. Thymol is a phenolic compound, which is extracted from thyme (20, 21). It exhibits antimicrobial and antifungal activities in a mechanism similar to that of CHX.…”

Transcriptional profiling reveals the molecular bases of immune regulation in Apis mellifera in response to Ascosphaera apis infection

“…apis infection at transcriptome level indicated clearly that the basic host-defense system in honey bees are complex, which includes many pathways and biological processes . In addition to these two pathways, the other immune pathways that are involved in responding to bacterial invasions have also been identified and activated in many other insects and animals , Evans et al 2006b, Shu et al 2016, Wong & Fish 2003. As with previous studies, these DEGs mainly involve in development, energy metabolism, signal transduction, immune system, and stimulus response.…”

Traditional Uses, Chemical Constituents and Biological Activities of Plants from the Genus Thymus

“…Thymol was able to disintegrate the outer membrane of Gram‐negative bacteria by releasing lipopolysaccharides (LPS) and increasing the permeability of the cytoplasmic membrane to regenerate adenosine triphosphate (ATP) . It could act through the function of the p38 mitogen‐activated protein kinase (MAPK) signaling pathway to protect against C. albicans infection and maintain the host innate immune response to C. albicans …”

“…[98] It could act through the function of the p38 mitogen-activated protein kinase (MAPK) signaling pathway to protect against C. albicans infection and maintain the host innate immune response to C. albicans. [99] Due to the remarkable antimicrobial activity, Thymus EOs have been widely applied in various fields in the form of micro-and nanocarriers, such as microemulsion and liposome. These new carriers exhibit excellent advantages for prolonging the shelf life in the storage of foods.…”