The Role of miRNA167 in Skin Improvement: Insight from Extracellular Vesicles Derived from Rock Samphire (Crithmum maritimum).

Samphire (Crithmum matrimum), a halophyte, thrives in saline environments due to its salt tolerance, which is partly attributed to miR167. However, the functional role of miR167 in human cells is unclear. This study explores the role of extracellular vesicles (EVs) derived from C. matrimum callus in skin regeneration, highlighting the potential of miRNA tae-miR167c-5p (miR167). Calluses were successfully induced and scaled for EV isolation. Characterization confirmed the presence of plant EV biomarkers and EVs with an average size of 136.6 nm. Cm-callus EVs enhanced wound healing and skin regeneration in human fibroblasts (HFF cells and CCD-986Sk cells) by modulating key genes, in particular, by downregulating MMP1 and upregulating COL1A1 and VEGFA. Small RNA sequencing revealed an enrichment of miR167 in Cm-callus EVs. Transfection with an miR167 mimic replicated these regenerative effects. Computational predictions identified PPP3R2, which is linked to the MAPK and NFAT pathways, as a potential target of miR167. This study demonstrates the efficacy of Cm-callus EVs and miR167 in promoting skin regeneration without cytotoxicity, providing insights into their therapeutic potential and calling for further experimental validation of target interactions.