Polyphenols enhance ATPase activity but not ATPase-driven lipophilic compound transport in rat liver membranes

DE ATHAYDE MONCORVO COLLADO, ALEJANDRO; SALAZAR, PAULA BELÉN; MORERO, ROBERTO; DUPUY, FERNANDO; MINAHK, CARLOS

Santiago del Estero

Congreso; XLIV Reunión Anual de la Sociedad Argentina de Biofísica; 2015

Biological membranes are complex and highly dynamic structures, responsible for critic functions such as maintaining an internal environment, transport of solutes and macromolecules; and signal reception and transduction. It is becoming increasingly evident that there is a important relationship between the physicochemical features of a membrane (which are highly regulated in living systems) and their biological properties. The presence of membranes-active substances, able to modulate their physicochemical properties could, therefore, activate or inhibit biological processes. Polyphenols, plant secondary metabolites characterized by the presence of phenolic groups, are potential candidates for this role. In this work, the ability of four chemically different polyphenols (resveratrol, naringenin, epigallocatechin gallate and enterodiol) to interact and modulate the viscosity and to modify biological activities will be studied.Fluorescence anisotropy studies showed that the presence of polyphenols was able to subtly modulate the viscosity of the aforementioned membranes. Enterodiol and, to a lesser extent, resveratrol were able to increase ATPase activity of rat liver membranes on in vitro assays, as determined by Ames-Chem method. Interestingly, no activation on nonespecific translocation of the fluorescent membrane probe TMA-DPH was observed in the presence of all four polyphenols studied.Results presented in this work indicate that polyphenols are not only able to interact closely with biological membranes; but also suggest that at least ATPase activity is significantly enhanced in their presence. Nevertheless, further studies will be needed to completely elucidate if the changes in the fluidity of the membranes are causing this promising and potentially relevant effect.