Evaluation of the cytotoxic activity and types of death in human cells strain after treatment with herbal products derived from Baccharis trimera (Less.) DC.

Author(s)

Isabela Jacob Moro

• Document type: Master's Dissertation
• Press: Araraquara. 2016-07-28.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências Farmacêuticas. Araraquara
• Defense date: 2016-06-23
• Advisor: André Gonzaga dos Santos; Christiane Pienna Soares

Abstract

Natural products diversity is an important source to find potential treatments against various diseases, including cancer. Vincristine and vimblastine, alkaloids derived from Catharantus roseus (L.) L. Don, are some of the examples. The structural diversity of molecules from plant species allow the in natura usage and also the development of other chemical entities that will be used to diseases control. Baccharis trimera (Less.) DC., popularly known as carqueja, has an extensive traditional use, especially for digestive disorders. The aims of this study were the chromatographic fractionation of aerial parts from carqueja, in vitro evaluation of the cytotoxic potential through sulforhodamine B assay and cellular death by Annexin-V assay, Hoechst/propidium iodide method and caspase-3 activation, in normal and tumor cell lines treated with essential oil, its fractions and components, and the flavone eupatorin isolated from ethyl acetate extract. The cell lines used were human breast cancer (MCF-7), hepatocellular carcinoma (HepG2) and normal breast line (MCF-10a). The evaluated samples were: essential oil, its fractions and components (α-humulene, β- caryophyllene and caryophyllene oxide) and eupatorin. The major constituents of the essential oil identified by GC-MS were: β-caryophyllene (18.9%), bicyclogermacrene (15.6%), germacrene D (10.5%), δ-cadinene (6.6%). Other components of the essential oil, such as α-humulene (2.3%) and caryophyllene oxide (2.9%) were also identified. The essential oil fractions were obtained by column chromatography (silica gel) and analyzed by GC-FID and GC-MS, presenting different chemical compositions. The flavone eupatorin (96% purity in 250 nm; w/w) was isolated from ethyl acetate extract using preparative thin layer chromatography (silica gel) and identified by spectrometric methods (MS, UV, 1H and 13C NMR). The largest decrease in cell viability for HepG2 was observed with essential oil (IC50 = 10.40 μg / mL); α-humulene and trans-caryophyllene for MCF7 cells (IC50 7.59 and 11.52 μg / mL, respectively) and eupatorin for MCF10A (IC50= 5.08 μg / mL). IC50 for eupatorin in MCF7 cells was 6.73 μg / mL. Most of the essential oils fractions were cytotoxic to the cell lines and higher concentrations were required to achieve IC50. There was not a cell death standard since apoptosis and necrosis occurred as well. Statistical significance was not found in caspase-3 assay. Chromatographic techniques were efficient for compounds identification and separation, and spectrometry techniques for structural determination of eupatorin. The results from this research shown therapeutic potential against cancer for the studied samples. (AU)

• FAPESP's process: 14/10552-3 - Evaluation of the cytotoxic activity and types of death in human cells strain after treatment with herbal products derived from Baccharis trimera (Less.) DC
• Grantee: Isabela Jacob Moro
• Support Opportunities: Scholarships in Brazil - Master