Dendrobium officinale nanovesicles: transcriptomic landscape and anti-inflammatory roles

Plant-derived extracellular vesicle-like nanoparticles (EVLNs) represent a promising category of natural nanocarriers with significant potential for therapeutic applications. Nevertheless, the physicochemical properties and pharmacological functions of vesicles derived from Dendrobium officinale (Do-EVLNs) remain inadequately characterized. This study systematically elucidates the structural characteristics, in vitro regenerative and anti-inflammatory functions, and the comprehensive whole-transcriptome molecular landscape of Do-EVLNs.

Do-EVLNs were isolated through differential ultracentrifugation. Physicochemical characterization was conducted to detect vesicle properties. In vitro cellular assays were performed to evaluate cellular uptake, biological function of Do-EVLNs in human skin cells. Lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages were used for in vitro anti-inflammatory assessment. Comprehensive strand-specific transcriptomic profiling (miRNAs, lncRNAs, mRNAs, and circRNAs) and differential expression analysis together with bioinformatic functional enrichment analyses were carried out.

Physicochemical characterization revealed spherical vesicles with a mean diameter of 132.1 ± 1.9 nm, a stable yield of 5.7 × 10¹⁰ particles/mL, and a negative zeta potential of -24 ± 0.16 mV. In vitro cellular assays confirmed efficient internalization of Do-EVLNs by key human-skin-resident cells (HUVECs, HACAT cells, and BJ-1 cells). Functionally, Do-EVLNs demonstrated excellent biocompatibility and significantly enhanced tissue repair phenotypes, notably improving the wound closure rate by over 40% within 24 h (p < 0.05), stimulating capillary-like network formation, and reducing apoptosis through the promotion of the G1-to-S cell-cycle transition. Importantly, in vitro anti-inflammatory assessment in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages indicated that Do-EVLNs exhibited no cytotoxicity at concentrations of 5-20 μg/mL. Upon treatment, Do-EVLNs substantially suppressed inflammation by reversing the transcriptional and translational expression of interleukin-6 (IL-6) in a dose-dependent manner, returning protein secretion to levels approaching those of the baseline vehicle control, while concurrently promoting the upregulation of the anti-inflammatory cytokine IL-10. Comprehensive strand-specific transcriptomic profiling uncovered a highly selective nucleic acid packaging mechanism unique to the EVLNs, distinct from parental tissues. Differential expression analysis identified an enriched and complex cargo in Do-EVLNs, including 1,163 upregulated miRNAs (notably inflammation-resolving markers such as miR-223-5p and the miR-169 family), 2,188 lncRNAs, and 5,505 mRNAs (p < 0.05). Bioinformatic functional enrichment analyses suggested that these specialized molecular cargoes are likely to modulate critical host signaling pathways, particularly the PI3K/AKT pathway, cellular metabolism, and cytoskeletal remodeling, which are crucial in mediating inflammatory responses.

These quantitative findings lay a solid foundation for the upcoming development of Do-EVLNs as novel bioactive nanotherapeutics aimed at promoting skin homeostasis and enhancing wound healing.