Lipid nanostructures for antioxidant delivery: a comparative preformulation study

Elisabetta Esposito; Maddalena Sguizzato; Markus Drechsler; Paolo Mariani; Federica Carducci; Claudio Nastruzzi; Giuseppe Valacchi; Rita Cortesi

doi:10.3762/bjnano.10.174

Lipid nanostructures for antioxidant delivery: a comparative preformulation study

Beilstein J Nanotechnol. 2019 Aug 29:10:1789-1801. doi: 10.3762/bjnano.10.174. eCollection 2019.

Authors

Elisabetta Esposito¹, Maddalena Sguizzato¹, Markus Drechsler², Paolo Mariani³, Federica Carducci³, Claudio Nastruzzi¹, Giuseppe Valacchi^{4

5

6}, Rita Cortesi¹

Affiliations

¹ Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, I-44121 Ferrara, Italy.
² Bavarian Polymerinstitute "Electron and Optical Microscopy" University of Bayreuth, Germany.
³ Dipartmento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, I-60131 Ancona, Italy.
⁴ NC State University, Plants for Human Health Institute, Animal Science Dept. NC Research Campus, Kannapolis, NC 28081, USA.
⁵ Department of Biomedical and Specialist Surgical Sciences, University of Ferrara, I-44121 Ferrara, Italy.
⁶ Department of Food and Nutrition, Kyung Hee University, Seoul, Korea.

Abstract

This investigation is a study of new lipid nanoparticles for cutaneous antioxidant delivery. Several molecules, such as α-tocopherol and retinoic acid, have been shown to improve skin condition and even counteract the effects of exogenous stress factors such as smoking on skin aging. This work describes the design and development of lipid nanoparticles containing antioxidant agents (α-tocopherol or retinoic acid) to protect human skin against pollutants. Namely, solid lipid nanoparticles and nanostructured lipid carriers were prepared using different lipids (tristearin, compritol, precirol or suppocire) in the presence or absence of caprylic/capric triglycerides. The formulations were characterized by particle size analysis, cryogenic transmission electron microscopy, small-angle X-ray diffraction, encapsulation efficiency, preliminary stability, in vitro cytotoxicity and protection against cigarette smoke. Nanostructured lipid carriers were found to reduce agglomerate formation and provided better dimensional stability, as compared to solid lipid nanoparticles, suggesting their suitability for antioxidant loading. Based on the preformulation study, tristearin-based nanostructured lipid carriers loaded with α-tocopherol were selected for ex vivo studies since they displayed superior physico-chemical properties as compared to the other nanostructured lipid carriers compositions. Human skin explants were treated with α-tocopherol-loaded nanostructured lipid carriers and then exposed to cigarette smoke, and the protein levels of the stress-induced enzyme heme oxygenase were analyzed in skin homogenates. Interestingly, it was found that pretreatment with the nanoformulation resulted in significantly reduced heme oxygenase upregulation as compared to control samples, suggesting a protective effect provided by the nanoparticles.

Keywords: HO-1; cryogenic transmission electron microscopy (cryo-TEM); dermocosmetics; nanostructured lipid carriers (NLCs); retinoic acid; skin pollution; solid lipid nanoparticles (SLNs); α-tocopherol.