Antiproliferative activity of ionic liquid-graviola fruit extract against human breast cancer (MCF-7) cell lines using flow cytometry techniques.

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants have been used for ages by indigenous communities around the world to help humankind sustain its health. Graviola (Annona muricata), also called soursop, is a member of the Annonaceae family and is an evergreen plant that is generally distributed in tropical and subtropical areas of the world. Graviola tree has a long history of traditional use due to its therapeutic potential including anti-inflammatory, antimicrobial, antioxidant, insecticide and cytotoxic to tumor cells. AIM OF THE STUDY: This study aimed to investigate the in vitro antiproliferative effects and apoptotic events of the ionic liquid extract of Graviola fruit (IL-GFE) on MCF-7 breast cancer cells and their cytokinetics behaviour to observe their potential as a therapeutic alternative in cancer treatment. MATERIALS AND METHODS: The cell viability assay of the extract was measured using tetrazolium bromide (MTT assay) to observe the effects of Graviola fruit extract. Then the cytokinetics behaviour of MCF-7 cells treated with IL-GFE is observed by plotting the growth curve of the cells. Additionally, the cell cycle distribution and apoptosis mechanism of IL-GFE action on MCF-7 cancer cells were observed by flow cytometry. RESULTS: IL-GFE exhibited anti-proliferative activity on MCF-7 with the IC50 value of 4.75 µg/mL, compared to Taxol with an IC50 value of 0.99 µg/mL. IL- GFE also reduced the number of cell generations from 3.71 to 1.67 generations compared to 2.18 generations when treated with Taxol. Furthermore, the anti-proliferative activities were verified when the growth rate was decreased dynamically from 0.0077 h to 1 to 0.0035 h-1. Observation of the IL-GFE-treated MCF-7 under microscope demonstrated detachment of cells and loss of density. The growth inhibition of the cells by extracts was associated with cell cycle arrest at the G0/G1 phase, and phosphatidylserine externalisation confirms the anti-proliferation through apoptosis. CONCLUSIONS: ionic liquid Graviola fruit extract affect the cytokinetics behaviour of MCF-7 cells by reducing cell viability, induce apoptosis and cell cycle arrest at the G0/G1 phase.

Trypanosomatid phosphoglycerate mutases have multiple conformational and oligomeric states.

Three structurally distinct forms of phosphoglycerate mutase from the trypanosomatid parasite Leishmania mexicana were isolated by standard procedures of bacterial expression and purification. Analytical size-exclusion chromatography coupled to a multi-angle scattering detector detected two monomeric forms of differing hydrodynamic radii, as well as a dimeric form. Structural comparisons of holoenzyme and apoenzyme trypanosomatid cofactor-independent phosphoglycerate mutase (iPGAM) X-ray crystal structures show a large conformational change between the open (apoenzyme) and closed (holoenzyme) forms accounting for the different monomer hydrodynamic radii. Until now iPGAM from trypanosomatids was considered to be only monomeric, but results presented here show the appearance of a dimeric form. Taken together, these observations are important for the choice of screening strategies to identify inhibitors of iPGAM for parasite chemotherapy and highlight the need to select the most biologically or functionally relevant form of the purified enzyme.