Antitumour and Antimetastatic Effects and Safety Profile of a New Magnesium(II)-Chrysin Complex

Abstract

Chrysin is a flavone found in many plant extracts including blue passion flower, propolis and honey. The magnesium(II) cation is an essential metal for life and it is involved in a variety of metabolic and physiological functions. Biological activities of flavonoids can be improved by complexation with metals. For this reason, Mgchrys was synthesised. The complex was characterised by spectroscopic techniques (ultraviolet-visible absorption spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), 1H and 13C-NMR) and elemental and thermogravimetric analysis. The results indicated that chrysin reacts with magnesium(II) through a 4-carbonyl-5-hydroxy chelation site. The computational study suggests the coexistence of at least twelve conformers of Mgchrys at room temperature. There are six most stable conformers that show square-pyramidal and distorted square-pyramidal geometries. In addition, anticancer and antimetastatic activities of Mgchrys on the A549 cell line were evaluated and compared with the metal and the free ligand. The complex did not show cytotoxicity against normal lung fibroblasts but it behaved as a cytotoxic drug against the cancer cell line with oxidative stress being its probable mechanism of action. However, Mgchrys inhibited the different steps involved in the metastatic cascade: Adhesion to fibronectin, migration and invasion. The compounds displayed no acute toxicity (Artemia salina test) and no mutagenic effect (Ames test).