Phytochemical profiling and multi-target bioinformatics analysis of gentiopicroside-rich Gentiana veitchiorum Hemsl. flowers extract with in vitro/in vivo evidence of skin barrier repair, soothing and moisturizing benefits

Gentiana veitchiorum Hemsl. is a significant plant in traditional Tibetan medicine, mostly renowned for its virtues to treat smallpox, tracheitis, and cough. To pioneer a new pathway to develop G. veitchiorum as a sustainable skin barrier-protective ingredient, hot-water extracts from roots, stems, leaves, flowers, and whole plants of GV were assessed. HPLC profiling demonstrated that the Gentiana veitchiorum Hemsl. flower extract (GVFE) was the most bioactive fraction of G. veitchiorum, containing the highest levels of gentiopicroside (15.5%), isoorientin (1.9%), and isovitexin (1.7%), as well as the greatest yield rate extraction (50.15%) compared to the roots (32.10%), stems (24.80%), leaves (40.35%), and the whole plant (39.00%) extracts. In silico molecular docking predicted strong binding of gentiopicroside to skin receptors associated with skin repair, soothing, and moisturisation. In vitro and in vivo experiments evaluated the multi-target potency of gentiopicroside from GVFE over predicted skin biological activities. In vitro assays on keratinocytes (KCs) showed that GVFE (0.01%, 0.05%) significantly increased CLDN1 (55.0%, 210.0%), ZO-1 (36.0%, 69.0%), AQP3 (166.0%, 335.0%), and GBA1 (22.0%, 82.0%) mRNA expressions in keratinocytes, while gentiopicroside (0.0015%, 0.0075%) also upregulated these markers, including AQP3 (165.0%) and (176.0%). In vivo efficacy assessments showed on day 7 and then day 14 that GVFE significantly increased the skin stratum corneum water content (27.1%; 42.1%) and decreased trans epidermal water loss (TEWL) (14.5%; 25.0%). In THP-1 cells, IL-8 mRNA expression was reduced by GVFE (28.9 and 52.9%) and gentiopicroside (41.7 and 43.1%). TRPV1 mRNA expression was also suppressed by GVFE at 0.01% and 0.05% (27.3 and 18.0%, respectively) and by gentiopicroside at 0.0075% (10.7%). GVFE inhibited prostaglandin E2 (PGE2) secretion (18.6%; 22.9%), whereas gentiopicroside showed inhibition rates (27.3%; 26.7%). To date, research on GVFE and its skin benefits remains limited. Our study could fill this research gap and demonstrate that GVFE exerts potent benefits on skin barrier repair and soothing, with gentiopicroside identified as a key bioactive component; the potential contributions of co-occurring flavonoids (isoorientin and isovitexin) to the overall efficacy of the extract remain yet to be fully elucidated. GVFE possesses promising potential as an innovative natural cosmetic ingredient in the future.