Reduced phagocytosis, ROS production and enhanced apoptosis of leukocytes upon alcohol drinking in healthy volunteers

BACKGROUND: Alcohol drinking is associated with a serious risk of developing health problems as well as with a large number of traumatic injuries. Although chronic alcohol misuse is known to contribute to severe inflammatory complications, the effects of an acute alcohol misuse are still unclear. Here, the impact of acute alcohol drinking on leukocyte counts and their cellular functions were studied. METHODS: Twenty-two healthy volunteers (12 female, 10 male) received a predefined amount of a whiskey-cola mixed drink (40% v/v), at intervals of 20 min, over 4 h to achieve a blood alcohol concentration of 1‰. Blood samples were taken before drinking T(0), 2 h (T(2)), 4 h (T(4)), 6 h (T(6)), 24 h (T(24)) and 48 h (T(48)) after starting drinking alcohol. Leukocytes, monocytes and granulocyte counts and their functions regarding the production of reactive oxidative species (ROS), phagocytosis and apoptosis were analyzed by flow cytometry. RESULTS: Total leukocyte counts significantly increased at T(2) and T(4), while granulocyte and monocyte counts decreased at T(4) and T(6) vs. T(0). Monocytes increased significantly at T(24) and T(48) vs. T(0). While the total number of ROS-producing leukocytes and notably granulocytes significantly increased, in parallel, the intracellular ROS intensity decreased at T(2) and T(6). The numbers of ROS-positive monocytes have shown a delayed modulation of ROS, with a significant reduction in the total number of ROS-producing cells at T(48) and a significantly reduced intracellular ROS-intensity at T(24). Phagocyting capacity of leukocytes significantly decreased at T(4) and T(6). In general leukocytes, and notably granulocytes demonstrated significantly increased early (T(2)), while monocyte exerted significantly increased late apoptosis (T(24) and T(48)). CONCLUSIONS: Alcohol drinking immediately impacts leukocyte functions, while the impact on monocytes occurs at even later time points. Thus, even in young healthy subjects, alcohol drinking induces immunological changes that are associated with diminished functions of innate immune cells that persist for days.