Cosm-nutraceutical nanovesicles for acne treatment: physicochemical characterization and exploratory clinical experimentation

The full exploration of the 'nutraceuticals' therapeutic potential in cosmetics has been hindered by their poor stratum corneum permeation. Therefore, the aim of the present study was to formulate a nutraceutical; quercetin, in novel vitamin C based nanovesicles (aspasomes), and to explore their beneficial effects in the treatment of acne. Aspasomes were characterized for their particle size, zeta potential, entrapment efficiency (EE%), 3-months storage stability, skin deposition/permeation, antioxidant potential, and morphology. Aspasomes antibacterial efficacy on 'Propionibacterium acnes' using the zone of inhibition assay was also tested, whilst their safety on skin fibroblastic cells was assessed in vitro using 3T3 CCL92 cell lines. An exploratory clinical trial was conducted in acne patients, and the percentage reduction of inflammatory, non-inflammatory and total acne lesions was taken as the evaluation criterion. Results revealed that quercetin-loaded aspasomes displayed a desirable nanometer size (125-184 nm), negative charge with good storage stability, and high skin deposition reaching 40%. Aspasomes managed to preserve the antioxidant activity of quercetin, and exhibited a significantly higher antibacterial effect (15 ± 1.53 mm) against 'Propionibacterium acnes' than quercetin alone (8.25 ± 2.08 mm), and were safe on skin fibroblastic cells. Upon clinical examination in 20 acne patients (14 females, 6 males), quercetin aspasomes exhibited reduction percentages of 77.9%, 11.8% and 55.3% for inflammatory lesions, comedones and total lesions respectively. This opens vast applications of the presented formulation in the treatment of other oxidative skin diseases, and delineates the nutraceuticals and nanoformulations prepared from natural materials as promising dermatological treatment modes.