Carreadores lipídicos nanoestruturados que encapsulam óleos essenciais como potencial tratamento contra Alzheimer em modelo de drosophila melanogaster

Abstract

The Alzheimer disease (AD) is characterized by the accumulation of amyloid beta (Aβ) protein plaques, tau protein tangles and neurodegeneration. There are a few approved drugs for the AD treatment and none of them promotes the cure, in addition to cause several systemic side effects. Essential oils (EO) have several interesting pharmacological properties for drug development, but they present physicochemical limitations (hydrophobicity, photosensitivity, instability and high volatility) that can be improved through nanoencapsulation. Among the nanocarriers systems, nanostructured lipid carriers (NLC) are very promising in the EO delivery, being stable, biocompatible, increase the bioavailability, reducing the toxicity. The objective of this work was the development of NLC formulations encapsulating EO. NLC were based on vegetable butter (shea) and essential oils (copaiba or frankincense) as the lipid phase and poloxamer 188 as a surfactant in the aqueous phase. They were evaluated for physicochemical stability in terms of size (nm), polydispersity index (PDI) and Zeta potential (mV), for 365 days at 25 ºC (n=3). The formulations were stable for 365 days at 25 ºC and have showed homogeneous particle size distribution and expected average sizes. EO have contributed to reducing particle sizes, also confirming their structural role in NLC. The safe and effective NLC concentrations were determined for D. melanogaster. The formulations have showed anti-neurodegenerative activity, reducing the accumulation of Aβ protein and neuronal death in the optic lobe medulla of flies. Even the NLC control (without EO) was able to reduce degeneration, demonstrating the bioactivity of shea butter. This work was a pioneer in developing NLC carrying copaiba and frankincense EO for the Alzheimer treatment. Further assays should be conducted on more complex biological models, in order to ensure the safety and efficacy of these promising systems for the treatment of AD.