Red sacaca essential oil-loaded nanostructured lipid carriers optimized by factorial design: cytotoxicity and cellular reactive oxygen species levels

Sofia Santos Donaire Chura; Kathelen Anne Sudo Memória; Amanda Tibães Lopes; Franciele Maria Pelissari; João Vinícios Wirbitzki Da Silveira; Jaqueline de Araújo Bezerra; Francisco Celio Maia Chaves; Ana Paula Rodrigues; Jerusa Araújo Quintão Arantes Faria; Guilherme Carneiro

doi:10.3389/fphar.2023.1176629

Red sacaca essential oil-loaded nanostructured lipid carriers optimized by factorial design: cytotoxicity and cellular reactive oxygen species levels

Front Pharmacol. 2023 Oct 11:14:1176629. doi: 10.3389/fphar.2023.1176629. eCollection 2023.

Affiliations

¹ Department of Pharmacy, Faculty of Biological and Health Sciences, Federal University of Jequitinhonha and Mucuri Valleys, Diamantina, Brazil.
² Postgraduation Program in Basic and Applied Immunology, Federal University of Amazonas, Manaus, Brazil.
³ Institute of Science and Technology, Federal University of Jequitinhonha and Mucuri Valleys, Diamantina, Brazil.
⁴ Federal Institute of Education, Science and Technology of Amazonas (IFAM), IFAM Analytical Center, Manaus Centro Campus, Manaus, Brazil.
⁵ Embrapa Western Amazon, Manaus, Brazil.

^# Contributed equally.

Abstract

Amazonian flora includes several species with the potential to develop pharmaceutical and biotechnological products. The essential oils from Amazonian species possess some biological properties, such as antioxidant, antibacterial, and cytotoxic activities. The essential oil of red sacaca (RSO), Croton cajucara Benth., contains metabolites characterized by antioxidant and anti-inflammatory activities. Nanostructured lipid carriers (NLC) are an advantageous alternative for the effective delivery of drugs because they can solubilize lipophilic actives and reduce their cytotoxicity. This study aimed to optimize the synthesis of RSO-loaded nanostructured lipid carriers (NLC-RSO) using a 2³ factorial design and investigate their antioxidant and cytotoxic effects. The red sacaca essential oil (RSO) metabolite profile was characterized using gas chromatography coupled with a mass spectrometer (GC-MS), identifying 33 metabolites, with linalool and 7-hydroxy-calamenene as the major ones, as reported in the literature. The optimized NLC-RSO formulation had a particle size less than 100 nm and a polydispersity index lower than 0.25. After characterizing NLC-RSO using Fourier-transform infrared spectroscopy, powder X-ray diffraction, zeta potential, moisture content, and wettability, in vitro cytotoxicity were performed in A549 and BEAS-2B cell lines using the resazurin metabolism assay. The data indicated a lower IC50 for RSO than for NLC-RSOs in both cell lines. Furthermore, low cytotoxicity of blank nanoparticles (blank NP) and medium chain triglycerides-loaded nanostructured lipid carriers (NLC-MCT) towards both pulmonary cell lines was noted. At a concentration of 50-100 μg/mL, free RSO exhibited higher cytotoxicity than NLC-RSO, demonstrating the protective effect of this lipid carrier in reducing cytotoxicity during metabolite delivery. Similarly, free RSO showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging than NLC-RSO, also indicating this protective effect. The 2',7'-dichlorofluorescein diacetate (DCFH-DA) intracellular reactive oxygen species (ROS) level assay did not show differences between the treatments at higher but non-cytotoxic dosages. Taken together, our results suggest that NLC-RSOs are potential RSO delivery systems for applications related to cancer treatment.

Keywords: Croton cajucara Benth.; amazon plants; nanotechnology; plant metabolites; rotational central composite design.

Grants and funding

This work was funded by Fundação de Amparo à Pesquisa do Estado do Amazonas (FAPEAM) POSGRAD Program [#005/2022, #002/2023] and Universal Amazonas Program (#06/2019), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), and Fundação de Amparo à Pesquisa do Estado de Minas Gerais (Fapemig). KM have fellowships from CAPES (MSc students). SC received fellowship from CNPq (Scientific Initiation student).