In vitro effects of some gold complexes on Na(+)/K(+) ATPase activity and cell proliferation.

In vitro effects of some gold complexes on Na(+)/K(+) ATPase activity and cell proliferation. J Inorg Biochem. 2013 Mar 29;124C:35-41 Authors: Petrović V, Colović M, Krstić D, Vujačić A, Petrović S, Joksić G, Bugarčić Z, Vasić V Abstract The in vitro influence of gold(III) complexes, H[AuCl4], [Au(DMSO)2Cl2]Cl and [Au(bipy)Cl2]Cl (bipy = 2,2'-bipyridine), upon commercially available Na(+)/K(+) ATPase activity, purified from porcine brain cortex, was investigated. Additionally, the complexes were tested on human lymphocytes, and incidence of micronuclei and cell proliferation index was determined. Concentration-dependent inhibition of the enzyme for all three compounds was obtained, but with differing potencies. Calculated IC50 from Hill analysis were (in M): 5.75×10(-7), 5.50×10(-6) and 3.98×10(-5), for H[AuCl4], [Au(DMSO)2Cl2]Cl and [Au(bipy)Cl2]Cl, respectively, while Hill coefficient values, n, were above 1 in all cases. This inhibition can be prevented using -SH donating ligands such as L-Cys and glutathione, and these ligands can also cause a recovery of the enzyme activity after the induced inhibition. Kinetic analysis demonstrated that each of the studied gold(III) complexes affects Na(+)/K(+) ATPase reducing maximum enzymatic velocity, Vmax, but not significantly changing the affinity for the substrate (KM value), implying a noncompetitive mode of the interaction. Furthermore, among investigated gold(III) complexes, the [A...
Source: Journal of Inorganic Biochemistry - Category: Biochemistry Authors: Tags: J Inorg Biochem Source Type: research