Formulation and In Vitro Efficacy Assessment of Teucrium marum Extract Loading Hyalurosomes Enriched with Tween 80 and Glycerol.

The extract of Teucrium marum L. (Lamiaceae) was obtained using the aerial parts of the plant, by means of a maceration process. Verbascoside, caffeic acids derivatives and flavonols were the main components contained in the extract as detected using high-performance liquid chromatography coupled with diode array detector (HPLC-DAD) as an analytical method. The extract was successfully incorporated into hyalurosomes, which were further enriched by adding a water cosolvent (glycerol) and a surfactant (Tween 80), thus obtaining glycerohyalurosomes. Liposomes, transfersomes and glycerosomes were prepared as well and used as comparisons. All vesicles were small, as the mean diameter was never higher than ~115 nm, thus ideal for topical application and stable on storage, probably thanks to the highly negative surface charge of the vesicles (~-33 mV). The cryo-TEM images confirmed the formation of close-packed, oligolamellar and multicompartment hyalurosomes and glycerohyalurosomes in which around 95% of the used extract was retained, confirming their ability to simultaneously load a wide range of molecules having different chemical natures. Moreover, the extract, when loaded in hyalurosomes and glycerohyalurosomes was able to counteract the damages induced in the fibroblasts by hydrogen peroxide to a better extent (viability~110%) than that loaded in the other vesicles (viability~100%), and effectively promoted their proliferation and migration ensuring the healing of the wound performed in a cell monolayer (scratch assay) during 48 h of experiment. Overall in vitro results confirmed the potential of glycerohyalurosomes as delivery systems for T. marum extract for the treatment of skin lesions connected with oxidative stress.