miRNA408 from Camellia japonica L. Mediates Cross-Kingdom Regulation in Human Skin Recovery.

Wound healing is a complex and dynamic process involving several stages of tissue repair. This study has shown that extracellular vesicles (EVs) derived from the callus of Camellia japonica L. and their associated microRNAs (miRNAs) possess significant wound healing activities. In human fibroblasts, EVs from C. japonica L. stimulated wound healing and upregulated collagen gene expression. The EVs also decreased inflammation levels in human keratinocytes, supporting wound healing. Among the miRNAs identified, miR408, one of the abundant miRNAs in the EVs, also showed similar wound healing efficacy. These findings suggest that both EVs and miR408 from the callus of C. japonica L. play a pivotal role in promoting wound healing. Additionally, this study shows that the regulation of miRNAs between different kingdoms can be achieved and suggests a new direction for the utilization of plant-derived components.