Cytotoxicity screening and enhanced anti-cancer activity of essential oils-loaded nanoparticles against A549 lung and HCT-116 colon cancer cells

CASTRO M. A.; JUAN R. GIROTTI; CISNEROS SEBASTIAN; VIÑA S; CRESPO R; CASTRO GUILLERMO; C. VERICAT; ISLAN G; BORIS RODENAK KLADNIEW

Congreso; REUNIÓN CONJUNTA SAIC SAI&FAIC SAFIS 2022; 2022

Essential oils (EOs) from aromatic plants present several pharmacological activities including anti-cancer effects. EOs are low-cost, mostly non-toxic, and widely used in medicine, however, they show low bioavailability and are exposed to facile degradation by light, volatilization, and oxidation. Here, we designed EO-loaded solid lipid nanoparticles (SLN/EO), as a biocompatible system to deliver and improve EOs anticancer activity. Two cell models, A549 lung and HCT-116 colon cancer cells, were exposed for 24 h to 0-500 µL/L of eight different EOs obtained by hydrodistillation from leaves of local plants. Cell viability (MTT) was evaluated and IC50 were calculated. Lippia alba (EO2) and Clinopodium nepeta (EO3) were the two most active EOs in both cell lines. SLN containing EO2 (SLN/EO2) or EO3 (SLN/EO3) were prepared by hot melted-ultrasonication method. The morphology, size, z-potential (z-pot), and polydispersity index (PI) were determined by DLS and TEM. SLN/EOs showed spherical shape, sizes of 140-150 nm with narrow distribution (PI< 0.3), and negative z-pot (-5 to -13 mV). EO2 encapsulation decreased IC50 from 275 and 145 µL/L to 131 and 122 µL/L whereas EO3 encapsulation reduced IC50 from 205 and 200 µL/L to 66 and 134 µL/L in A549 and HCT-116 cells, respectively. SLN/EO3 and A549 cells were selected for the following experiments. The encapsulation efficiency (EE) and release of EO3 from SLN were measured by UV-vis spectrometry. The EE of EO3 was high (96.8%) and a controlled release was observed at acidic (5.0) and neutral (7.4) pH conditions. Cell death (Trypan Blue) and cell migration (Wound Healing) were evaluated. Encapsulation of EO3 increased cell death (from 1.3 and 3.4% to 12.6 and 16.0% at 50 and 100 µL/L, respectively, p<0.05) and cell migration inhibition (p<0.05). Moreover, SLN/EO3 up to 100 µL/L was non-toxic in normal lung fibroblasts. Our results suggest that SLN/EO3 is a promising bioactive tool for lung cancer treatment.