Characterization of a sub-lethal systemic dose of Shiga toxin 2 in the nervous system

TIRONI-FARINATI CARLA; CANGELOSI ADRIANA; GEOGHEGAN PATRICIA; MORRIS WINSTON; LOIDL C. FABIAN; PINTO ALIPIO; CEJUDO MARIA LAURA; GOLDSTEIN JORGE

Huerta Grande

Congreso; Second Joint Meeting of the Argentine Society for Neuroscience (SAN: XXV Reunión Anual de la Sociedad Argentina de Investigación en Neurociencias) and the Argentine Workshop in Neuroscience (TAN: XII Taller Argentino de Neurociencias); 2010

Sociedad Argentina de Investigación en Neurociencias

Neurological damage caused by intoxication with Shiga toxin (Stx) from enterohemorrhagic Escherichia coli is one of the most fatal outcomes of Hemolytic Uremic Syndrome in children. We have previously shown that intracerebroventricular (icv) administration of Stx2 damages rat brain neurons and astrocytes. The aim of this work was to determine the action of intraperitoneal (ip) Stx2 in the Nervous System. Mice brains and colons were processed to perform transmission electron microscopy (TEM) and fluorescence studies after 8 days of treatment. Apoptotic neurons and damaged astrocytes were observed in Stx2 (0,002 LD50) treated groups by TEM in the corpus striatum, cerebral cortex and hippocampus. This was not observed in controls. In addition apoptotic and degenerated oligodendrocytes, damaged endothelial cells with perivascular edema, synaptic inhibition and mitochondrial disorganization were observed. The preceded pathologic changes were not observed in the icv treated group. Significant neurodegeneration was confirmed by the Fluorojade-B method in the same brain areas and in the myenteric plexus. This study show differences in brain damage between the ip and icv administrations of Stx2. Systemic elements activated by Stx2 may increase the damage found in the Nervous System.