Fabrication of quercetin and curcumin bionanovesicles for the prevention and rapid regeneration of full-thickness skin defects on mice Ines Castangia a , Amparo Nácher b,c , Carla Caddeo a , Donatella Valenti a , Anna Maria Fadda a , Octavio Díez-Sales b,c , Amparo Ruiz-Saurí d , Maria Manconi a, / a Dept. Scienze della Vita e dell’Ambiente, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy b Dept. of Pharmacy and Pharmaceutical Technology, University of Valencia, Avda Vicente Andrés Estellés s/n, 46100-Burjassot, Valencia, Spain c Instituto de Reconocimiento Molecular y Desarrollo Tecnológico, Centro Mixto Universidad Politécnica de Valencia-Universidad de Valencia, Spain d Dept. of Pathology, University of Valencia, Avda Blasco Ibañez 17, 46010 Valencia, Spain article info Article history: Received 10 July 2013 Received in revised form 16 October 2013 Accepted 8 November 2013 Available online xxxx Keywords: Vesicles Polyphenols Skin inflammation Histopathology Wound healing abstract In the present work biocompatible quercetin and curcumin nanovesicles were developed as a novel approach to prevent and restore skin tissue defects on chronic cutaneous pathologies. Stable and suitable quercetin- and curcumin-loaded phospholipid vesicles, namely liposomes and penetration enhancer- containing vesicles (PEVs), were prepared. Vesicles were made from a highly biocompatible mixture of phospholipids and alternatively a natural polyphenol, quercetin or curcumin. Liposomes were obtained by adding water, while PEVs by adding polyethylene glycol 400 and Oramix Ò CG110 to the water phase. Transmission electron microscopy, cryogenic-transmission electron microscopy and small- and wide- angle X-ray scattering showed that vesicles were spherical, oligo- or multilamellar and small in size (112–220 nm). In vitro and in vivo tests underlined a good effectiveness of quercetin and curcumin nano- vesicles in counteracting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) induced lesions and inflammation. Myeloperoxydase activity, used to gauge inflammation, was markedly inhibited by quer- cetin liposomes (59%) and curcumin liposomes and polyethylene glycol (PEG)-PEVs (68%). Histology showed that PEG-PEVs provided an extensive re-epithelization of the TPA-damaged skin, with multiple layers of thick epidermis. In conclusion, nanoentrapped polyphenols prevented the formation of skin lesions abrogating the various biochemical processes that cause epithelial loss and skin damage. Ó 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. 1. Introduction Polyphenols are widely distributed in plants and plant-derived foods, including vegetables, fruits, tea, spices, wine, beverages and nutritional supplement products. In previous studies they have been proposed as therapeutic agents against several acute and chronic diseases, such as Alzheimer’s and Parkinson’s, multiple sclerosis, cardiovascular diseases, allergies and certain types of cancer [1]. These advantages are attributed to their useful antiox- idant and anti-inflammatory properties that regulate cell prolifer- ation and function by preventing the onset and progression of the aforementioned diseases [2–5]. Although phase I clinical trials have shown polyphenols as safe drugs even at high doses, poor bio- availability, poor absorption, rapid metabolism and systemic clear- ance hamper their use in pre-clinical and clinical models. Indeed, polyphenols such as curcumin, resveratrol and quercetin are poorly absorbed in the gastrointestinal tract and undergo rapid metabolization by the liver [1,6]. Moreover, clinical trials exploring different schedules of administration of polyphenols, especially quercetin and curcumin, have been hampered by their extreme water insolubility. To overcome such limitations, various natural polyphenols have been formulated in innovative nanovesicles to be administered by the dermal route [7–9]. The topical application of compounds with free-radical scavenging and anti-inflammatory properties in patients has shown a significant improvement in wound healing and protection from oxidative damage. In particu- lar, quercetin and curcumin may be promising for wound healing, thanks to their ability to inhibit reactive oxygen species and tissue inflammation [2,10–13]. A topical chronic non-healing wound is a complex multifacto- rial process involving the interplay of several cellular and biochem- ical mechanisms that compromise the viability of superficial tissues (epidermis and dermis). Inflammation, which constitutes a part of the acute response, results in a coordinated influx of neu- trophils at the wound site that produces and releases inflammatory mediators, such as tumor necrosis factor alpha (TNF-a) and inter- leukin-1 (IL-1). Neutrophils contain high levels of destructive pro- teases and oxygen free radicals that are released into the local wound area when cells die. This can cause extensive tissue damage 1742-7061/$ - see front matter Ó 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.actbio.2013.11.005 / Corresponding author. Tel.: +39 0706758542; fax: +39 0706758553. E-mail address: manconi@unica.it (M. Manconi). Acta Biomaterialia xxx (2013) xxx–xxx Contents lists available at ScienceDirect Acta Biomaterialia journal homepage: www.elsevier.com/locate/actabiomat Please cite this article in press as: Castangia I et al. Fabrication of quercetin and curcumin bionanovesicles for the prevention and rapid regeneration of full- thickness skin defects on mice. Acta Biomater (2013), http://dx.doi.org/10.1016/j.actbio.2013.11.005