Peppermint-Derived Extracellular Vesicles Promote Extracellular Matrix Synthesis and Suppress Matrix Metalloproteinase Expression in Human Dermal Fibroblasts.

OBJECTIVE: Peppermint-derived extracellular vesicles (PDEVs) represent a novel and unexplored class of plant-derived nanocarriers with potential bioactive properties. This study investigated effects of PDEVs on the viability, proliferation and function of human dermal fibroblasts (HDFs), as key players in wound healing. MATERIALS AND METHODS: In this experimental study, extracellular vesicles (EVs) were isolated from peppermint leaves via polyethylene glycol (PEG) precipitation. They were characterized using scanning electron microscopy (SEM) and dynamic light scattering (DLS). Protein content was quantified via Bradford assay. HDFs were treated with various concentrations of peppermint-derived EVs (1-20 μg/mL). Additionally, cell viability and proliferation were assessed using MTT assay and cell cycle analysis. Cell migration was evaluated using scratch assay. Furthermore, expression of the key extracellular matrix (ECM) remodeling genes (COL1A1, FN1, ELN, MMP1, MMP9) was analyzed using quantitative reveres transcription polymerase chain reaction (qRT-PCR). RESULTS: Peppermint-derived EVs (mean size 203 nm) significantly enhanced HDF proliferation and migration at 1 μg/ mL. Scratch assay demonstrated significantly accelerated wound closure in treated cells, reaching 91.75% closure at 24 hours compared to 75.24% in controls (P<0.001). Flow cytometry revealed an increased proportion of the cells in the S and G2 phases. Gene expression analysis demonstrated upregulation of COL1A1, FN1 and ELN, concurrent with downregulation of MMP1 and MMP9, indicative of positive ECM modulation. CONCLUSION: These findings suggest that peppermint-derived EVs may serve as promising bioactive agents for tissue regeneration, potentially contributing to development of plant-based therapeutics for wound healing.