Avaliação do potencial anti-inflamatório de carreadores lipídicos nanoestruturados carregados com óleo de sacaca vermelha

Abstract

The red sacaca, as the plant is popularly known (Croton cajucara Benth.) has stood out as a potential producer of essential oils with antioxidant and anti-inflammatory action. Seeking new ways to perform an effective delivery of drugs, nanostructured lipid carriers (NLC) have been presented as an advantageous option in prolonged release at the target site, in addition to solubilizing lipophilic actives and reducing their toxicity. The objective of this work was to characterize red sacaca oil (RSO) and evaluate the cytotoxic and antioxidant profile of lipid nanoparticles loaded with red sack oil (NLC_RSO) in A549 and BEAS-2B lung cell lines, and in THP-1 cells differentiated in macrophages. RSO characterization was performed by gas chromatography coupled to mass spectrometry (GC-MS). The viability profiles and 50% Inhibitory Concentration (IC50) values of NLC_RSO and RSO as well as the control groups Medium Chain Triacylglycerides (MCT), Nanoparticles Loaded with Medium Chain Triacylglycerides and Empty Nanoparticles (NLC_BLANK) were obtained through the assay of metabolization of the resazurin reagent and confirmed by trypan blue staining. The antioxidant activity was evaluated using a fluorescent probe 2′,7′-Dichlorofluorescein Diacetate (DCFDA). GC mass spectrometry analysis identified the presence of 33 OSV components, among which the most abundant metabolites were linalool and 7-hydroxy-calamene. The clonogenic assay was performed by staining with crystal violet. Treatment with NLC_RSO and RSO demonstrated a lower IC50 for RSO 59.84μg/ml ±29.30 (A549) and 18.91μg/ml ±13.48 (BEAS-2B) than for NLC_RSO 99.59 μg/ml ±27.71 (A549) and 83.87 μg /ml ±14.73 (BEAS-2B). THP-1 cells differentiated in macrophages treated with NLC_RSO showed a higher IC50 value than lung cell lines (IC50=134μg/ml±14.91). The highest non-cytotoxic concentration of NLC_RSO and RSO was 25μg/ml. OSV showed greater cytotoxicity when compared to NLC_RSO at the same concentrations. NLC_OSV tracked the levels of reactive oxygen species (ROS) in A549, while RSO increased the levels of ROS in BEAS-2B. The A549 strain was more resistant to RSO treatment than the BEAS-2B strain. RSO 25μg/ml does not reduce cell viability over 24, 42 and 78 hours. The 5μg/ml concentration of NLC_RSO showed an antiproliferative effect in the clonogenicity assay. RSO encapsulation confers oil protection and extended- release effect. Such data suggest as promising the approach of NLC_RSO as a potential delivery system for RSO. In addition, an expressive diversity of secondary metabolites in RSO associated with diverse biological functions support the potentiality of developing an RSO-based drug. This work corresponded to the initial study aimed at elucidating the application potential of lipid nanoparticles loaded with red sack oil. From the perspectives of the work, there is the characterization of the immunomodulatory profile of NLC_RSO in macrophages.