Plasma and mitochondrial membrane perturbation induced by aluminum in human peripheral blood lymphocytes

Abstract

Aluminum is a redox-inert element that could induce cell damage via activation of oxidative stress. In this work, the effect of aluminum on different cellular compartments of human peripheral blood lymphocytes was studied. The presence of aluminum induced a lipid peroxidation and physico-chemical modifications at the membrane level. A decrease in fluorescence anisotropy of TMA-DPH and in the polarity of the lipid bilayer with a concomitant shift toward a gel phase was observed, while the pyrene excimerization coefficient (Kex) increased. Flow cytometry measurements, using JC-1, Rhodamine 123 and H2-DCFDA as fluorescent probes, indicated that aluminum induces a slight mitochondrial membrane depolarization that was associated with a moderate increase in reactive oxygen species production. A significative influence on these parameters was measured only at high aluminum concentration.

Keywords: Aluminum; Human lymphocytes; Lipid peroxides; Membrane fluidity; Mitochondrial membrane depolarization; Reactive oxygen species.