Different Trypanosoma cruzi strains produce different alterations in mitochondria structure and the respiratory chain in the chagasic cardiomyopathy.

BÁEZ ALEJANDRA; LO PRESTI SILVINA; RIVAROLA WALTER; PONS PATRICIA; FRETES RICARDO; PAGLINI PATRICIA

Virtual

Congreso; V Congreso Internacional de Cardiología por Internet y V Congreso Virtual de Cardiología; 2007

Federación Argentina de Cardiología

Different  Trypanosoma cruzi  strains produce different alterations in mitochondria structure  and the respiratory chain in the chagasic cardiomyophaty. Báez Alejandra; Lo Presti Silvina; Rivarola Walter; Pons Patricia; Fretes Ricardo; Paglini Patricia. Cátedra de Física Biomédica, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Córdoba, Argentina.  Cátedras de Histología y de Microscopía Electrónica,  Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Córdoba, Argentina. Introduction: The entrance of Trypanosoma cruzi into cardiac cells generates immflamatory processes of variable magnitude and symptoms with the production of oxygen free radicals. This production increases when the mitochondrial respiratory I and III complexes (CI and CIII) are inhibited which in turns damages this organelle and the cell. Objetive: To study the relationship between mitochondrial damage and CI and CIII enzymatic activity in myocytes from mice infected with the different T. cruzi strains  in different moments of the infection. Material and method: 50 Albino Swiss mice were used and divided into the following groups, G1= non-infected (n=10); and infected with 50 trypomastigotes of Trypanosoma cruzi, G2= Tulahuen strain (n=20) and G3= SGO Z12 isolate (n=20). Cardiac tissue samples were obtained from every the group 10 and 365 days post-infection (d.p.i.), and were analyzed using a Zeiss electronic microscope. Mitochondria were isolated by subcelullar fractioning determining CI and CIII enzymatic activity by spectrophotometry. Results: Mitochondrial structure: Both infected groups presented alterations but they were less frequent in G3. Disorganized, undefined and dilated cristae were found 10 d.p.i.; and membrane disruption, dilated cristae and decrease in mitochondrial number were observed  365 d.p.i. Enzymatic activity (¦Ìm.min-1/mg prot): G1: CI = 0.05¡À0.02 ;  G2 and G3: CI was increased 10 d.p.i  and decreased 365 d.p.i. (p