RESUMO
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.
Assuntos
Alumínio/toxicidade , Membrana Celular/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Adulto , Alumínio/sangue , Benzimidazóis/metabolismo , Carbocianinas/metabolismo , Membrana Celular/química , Células Cultivadas , Polarização de Fluorescência , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Linfócitos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pessoa de Meia-Idade , Membranas Mitocondriais/química , Espécies Reativas de Oxigênio/metabolismo , Rodamina 123/metabolismoRESUMO
Aluminum belongs to a group of potential toxic elements capable of penetrating the human body. In this paper, the effect of aluminum concentrations on red blood cell membranes using different fluorescent probes able to localize in various parts of the phospholipid bilayer (TMA-DPH, laurdan and pyrene) were studied. Our results confirm that human erythrocytes exposed to aluminum undergo 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, and the pyrene excimerization coefficient (kex) increased. Furthermore, the presence of aluminum induced lipid peroxidation and reduced the activity of erythrocyte antioxidant enzymes (SOD, CAT and GSHPx). Al-induced morphological changes on the erythrocyte membrane surface were monitored using atomic force microscopy. These results provide further information on the target of action of different aluminum amounts.
