Experimental and theoretical insights of functionalized hexavanadates on Na+/K+-ATPase activity; molecular interaction field, ab initio calculations and in vitro assays.

The influence of three functionalized hexavanadates (V6): Na2 [V6O13{(OCH2)3CCH3}2], [H2]2 [V6O13{(OCH2)3CCH2OCOCH2CH3}2] and [(C4H9)4N]2 [V6O13{(OCH2)3CCH2OOC(CH3)2-COOH}2 on Na+/K+-ATPase activity, was investigated in vitro. Including compounds already tested by Xu et al. (Journal of Inorganic Biochemistry 161 (2016) 27-36), all functionalized hexavanadates inhibit the activity of Na+/K+-ATPase in a dose-dependent manner but with different inhibitory potencies. Na2 [V6O13{(OCH2)3CCH3}2] was found to have the best inhibition properties - showing 50% inhibition IC50 = 5.50 × 10-5 M, while [(C4H9)4N]2 [V6O13{(OCH2)3CCH2OOC(CH3)2-COOH}2] showed the lowest inhibitory power, IC50 = 1.31 × 10-4 M. In order to understand the bioactivity of functionalized hexavanadates series, we have also used a combined theoretical approach: determination of electrostatic potential from ab initio theoretical calculations and computation of the molecular interaction field (MIF) surface.