Unveiling acne microbiome signatures: the role of the microbiome and the impact of a facewash formula containing plant-derived monoterpenes.

BACKGROUND

Acne vulgaris is a common skin disorder associated with a dysbiotic skin microbiome. While changes in the skin microbiome profile in acne have been reported, its role in acne pathogenesis and resolution, as well as the potential to rebalance the acne microbiome through facewash products, remain to be elucidated.

OBJECTIVES

To investigate the microbiome signatures of participants with acne, at baseline and 4 weeks after intervention with a facewash product containing plant-derived monoterpenes, and 1 week after a regression phase with no product application.

METHODS

Volunteers with mild-to-moderate acne or without acne were recruited and balanced by age and gender for the ethics-approved, balanced, 4-week intervention and 1-week regression study. Participants with acne applied a marketed facial cleanser product containing plant-derived monoterpenes twice daily for 4 weeks. Participants without acne used a marketed mild face cleanser as control. Facial buffer scrub samples were taken just before product application (baseline), 4 weeks after product application and a 1-week regression phase for microbiome analysis. The absolute numbers of predominant bacteria Cutibacterium acnes and Staphylococcus epidermidis were determined by quantitative polymerase chain reaction. The facial microbiome profiles were investigated by 16 s V1-V3 amplicon sequencing and analysed using QIIME pipeline and SpiecEasi.

RESULTS

A significant increase was seen in the dominant bacteria burden with reduced microbiome diversity in people with acne compared with those without acne. At the microbiome community level, a notably fragile microbiome connectivity and changes in the dominant skin bacteria subnetwork were seen in individuals with acne. A topical intervention with a facewash containing plant-derived monoterpenes significantly reduced the dominant bacteria burden in acne. The treatment also improved microbiome diversity, as well as the network resiliency. These effects lasted even after stopping the treatment for a week.

CONCLUSIONS

Our findings reveal a new dimension in understanding the differences in the acne microbiome and provide new evidence on the use of topical interventions for improving the dysbiotic status of the acne microbiome which could aid in relieving acne symptoms.