Bacterias lácticas inmunomoduladoras en la regulación en la regulación de las alteraciones hemostáticas inducidas durante una infección respiratoria en huésped inmunosuprimido por desnutrición. Mecanismos básicos de acción

Abstract

Malnutrition induces a decrease in immunity that affects the ability of the organism to deal with an infectious challenge. The clotting system is considered a branch of immunity and its activation is important in the pathogenesis of an infectious disease. This work was conducted to determine coagulation modifications in malnourished hosts before and during infection. Weaned mice were malnourished via a protein-free diet. Well-nourished control mice (WNC) consumed a balanced conventional diet. Malnourished mice (MN) and WNC were challenged intranasally with Streptococcus pneumoniae. Blood, bronchoalveolar lavages (BAL), and lung samples were taken at different times post infection. The results were that MN showed altered hemostatic tests and fibrin(ogen) deposits in the lung. Thus, an increase in thrombin antithrombin complexes (TATc) in plasma and BAL was observed. In the MN group, infection induced a rise in TATc in plasma and BAL and increased plasma fibrinogen and fibrin(ogen) deposits in the lung. A decrease in activated protein C and antithrombin in BAL and an early decrease followed by an increase in plasma Factor VIII were also observed. Also MN demonstrated high levels of acute phase reactant and an increase in TNF-alfa. The feeding with a diet supplemented with Lactobacillus casei induced an anti-inflamatory cytokine pattern which contributed to limit coagulation activation and to normalize the regulatory protein. These findings will help to develop further strategies to reduce the damaging effects of clotting and enhance its beneficial contribution to immune reactions. Key words: malnourishment, blood coagulation, plasma, bronchoalveolar lavage, coagulation activation, coagulation inhibitors, TAT complexes.