Avaliação do efeito dos óleos essenciais de Ocimum Gratissimum e Mentha x Villosa em linhagem de células de adenocarcinoma humano de pulmão: citotoxicidade, ciclo celular e produção de TGF- β1

Abstract

Ocimum. gratissimum L. and Mentha x villosa Huds are aromatic plants largely used, in Brazil and other countries, for therapeutic and culinary purposes. Several pharmacological properties have been described for their essential oil and their major compounds: Eugenol and piperitenone oxide respectively. However, the antiproliferative effect and the blockage of the TGF-1 production are poorly understood. This cytokine contributes for the development of late-phase tumors. This study aimed to evaluate the effects of the essential oils of Ocimum gratissimum and Mentha x villosa over a TGF-1 producer human lung adenocarcinoma cell line. Methodology: Viability was assessed through MTT assay, on cell lineages (A549 and J774 A.1) and intraperitoneal macrophages treated for 48h with essential oil concentrations ranging from 5 to 200g/mL. Cell cycle and SubG1 DNA amount was evaluated through propidium iodide staining followed by flow citometry analysis. TUNEL assay was used to quantify the DNA fragmentation. ELISA was performed to measure the TGF-1 production. Results: Both essential oils reduced A549 cell viability (IC50: EOOG:160g/mL / EOMV:117g/mL), there was also cell cycle arrest at S phase, after 24hours of treatment (control: 12,31±0,89 / EOOG: 15,70±1,15 / EOMV: 23,35±0,75). SubG1 DNA amount was also elevated after treatment (control: 15,05±0,71 / EOOG: 91,94±1,71 / EOMV:24,62±1,06), an indicative of DNA fragmentation, one of the apoptosis sign. This effect was confirmed by the elevated TUNEL labeling. The non-lethal concentrations of the essential oils (10 and 50g/mL) led to the reduction of TGF-1 production. Conclusion: These data indicates the apoptotic and cell cycle arrest effects of the essential oils, mainly over TGF-1 producing tumors. As this cytokine has a key role over the survival and proliferation of these cancer cells. The possible systemic effects of these treatments are yet to be evaluated, as the TGF-1 blockage may affect the maintenance of homeostasis.