Pequi oil (Caryocar brasilense Cambess.) nanoemulsion alters cell proliferation and damages key organelles in triple-negative breast cancer cells in vitro

Abstract

Pequi oil is extracted from the fruit of a Brazilian native plant (Caryocar brasiliense Camb) that contains some molecules with anticancer potential. Due to its hydrophobic property, the administration of pequi oil associated with nanoemulsion systems represents a successful strategy to improve oil bioavailability. Breast cancer is the most frequent type of cancer among women and conventional therapies used are frequently associated with several side effects. Thus, the aim of this study was to investigate the effects of pequi oil-based nanoemulsion (PeNE) on triple-negative breast cancer cells (4T1), in vitro. PeNE presented a dose- and time-dependent cytotoxic effect with lower IC50 than free pequi oil after 48 h of exposure (p < 0.001). At 180 µg/mL, PeNE demonstrated numerous cell alterations, when compared to free pequi oil, such as morphological alterations, reduction in cell proliferation and total cell number, damage to plasmatic membrane, induction of lysosomal membrane permeability and depolarization of mitochondrial membrane, alteration of intracellular ROS production and calcium level, and increase in phosphatidylserine exposure. Taken together, the results suggest an interesting induction of cell death mechanisms involving a combined action of factors that impair nucleus, mitochondria, lysosome, and ER function. In addition, more pronounced effects were observed in cells treated by PeNE at 180 µg/mL when compared to free pequi oil, thereby reinforcing the advantages of using nanometric platforms. These promising results highlight the use of PeNE as a potential complementary therapeutic approach to be employed along with conventional treatments against breast cancer in the future.

Keywords

• Nanoemulsion
• Caryocar brasiliense
• Oil
• Breast cancer
• Cell death