Red blood cell deformability and alcohol dependence in humans

Studies of DPH fluorescence polarization and deformability have shown that alcohol induces rigidification of the red blood cell (RBC) membrane. We investigated a possible link between RBC membrane fluidity and deformability by studying both parameters simultaneously in samples from alcohol-dependent patients (group 1, N = 19), social drinkers (group 2, N = 12) and long-term abstaining alcoholics (group 3, N = 8). The active drinkers showed disturbances of several RBC membrane parameters, including abnormal microorganization of the membrane surface, a decrease in sialic acid content, and resistance to the fluidizing effect of ethanol, that were not completely corrected in the abstinent alcoholics. The RBC transit time was significantly longer in the active drinkers than in the abstainers but not the social drinkers. There were no significant differences between the groups with regard to membrane lipid core fluidity. The main abnormality (fluidization) in RBC from the active alcoholics involved the polar surface of the membrane (probed using TMA-DPH), and correlated with the decrease in sialic acid content but not with RBC deformability.