Nanostructured Ethosomal Gel Loaded with Arctostaphylosuva-Ursi Extract; In-Vitro/In-Vivo Evaluation as a Cosmeceutical Product for Skin Rejuvenation

Background: Arctostaphylosuva-ursi(AUU) being rich in polyphenols and arbutin is known to have promising biological activities and can be a potential candidate as a cosmaceutical. Ethosomes encourage the formation of lamellar-shaped vesicles with improved solubility and entrapment of many drugs including plant extracts. Objective: The objective of this work was to develop an optimized nanostructured ethosomal gel formulation loaded with AUU extract and evaluated for skin rejuvenation and depigmentation. Methods: AUU extract was tested for phenolic and flavonoid content, radical scavenging potential, reducing power activity, and in-vitro SPF (sun protection factor) estimation. AUU loaded 12 formulations were prepared and characterized by SEM (Scanning Electron Microscopy), vesicular size, zeta potential, and Entrapment Efficiency (%EE). The optimized formulation was subjected to noninvasive in-vivo investigations after incorporating it into the gel system and ensuring its stability and skin permeation. Results: Ethosomal vesicles were spherical in shape and Zeta size, zeta potential, PDI (Polydispersity Index), percentages of EE and in-vitro skin permeation of optimized formulation (F3) were found to be 114.7nm, -18.9mV, 0.492, 97.51±0.023%, and 79.88±0.013% respectively. AUU loaded ethosomal gel formulation was stable physicochemically and exhibited non-Newtonian behavior rheologically. Moreover, it significantly reduced skin erythema, melanin as well as sebum level and improved skin hydration and elasticity. Conclusion: A stable AUU based ethosomal gel formulation could be a better vehicle for phytoextracts than conventional formulations for cosmeceutical applications such as for skin rejuvenation and depigmentation.