Olea europaea leaf exosome-like nanovesicles encapsulated in a hyaluronic acid / tannic acid hydrogel dressing with dual “defense-repair” effects for treating skin photoaging

Photoaging, primarily caused by ultraviolet (UV) light, is the major factor in extrinsic skin aging. Existing anti-photoaging strategies mainly focus on early sun protection or repairing damaged skin, lacking a comprehensive treatment strategy. Therefore, this study developed a dressing that actively shields against UV radiation and repairs photoaged skin, offering double protection. This study utilized exosome-like nanovesicles derived from Olea europaea leaves (OLELNVs), enhancing them into a potent core biomaterial with high-dose effects and skin-friendly, non-cytotoxic inhibition of cell aging. These nanovesicles were incorporated into a cross-linked hyaluronic acid (HA) and tannic acid (TA) hydrogel with strong UV-absorbing properties, creating the OLELNVs@HA/TA hydrogel system. In vitro and in vivo experiments demonstrated that OLELNVs@HA/TA hydrogel can effectively reduce UV-induced skin damage and promote skin repair and regeneration. Additionally, RNA-seq and clustering analysis of miR168a-5p predicted targets revealed significant down-regulation of the NF-κB signaling pathway, mediating inflammatory aging responses. Overall, the OLELNVs@HA/TA hydrogel represents a novel dual-strategy approach for clinical application in combating photoaging.