Hepatic and intestine alteration in mice after oral low doses Microcystin-LR prolonged exposure.

SEDAN DANIELA; LAGUENS MARTIN; COPPARONI GUIDO; GIANNUZZI LEDA; ANDRINOLO DARÍO

Pilanesberg

Congreso; 9TH INTERNATIONAL CONFERENCE ON TOXIC CYANOBACTERIA; 2013

Nelson Mandela Metropolitan University

Background and aims: Injury caused by MC-LR prolonged intraperitoneal administration in animals was widely reported; however there are few studies on the effects of prolonged oral exposure to these toxins. Since the most important form of exposure to MC-LR is orally at low doses and for long periods, it is important to assess the real impact of MC-LR on health in these exposure conditions. The aim of this work was to study the toxic effects of MC-LR in a prolonged oral exposure to low doses in N: NIH-Swiss mice. Methods: MC-LR was purified from natural blooms of Microcystis aeruginosa and quantified by HPLC-DAD. Two groups of 6 mice were treated with 100 μgMC-LR/kg and 50 μgMC-LR/kg body weight by gavage every 48 h during 1 month. Liver, kidney, intestine, lung and heart histological studies (Hematoxylin & Eosin, Red Oil, PAS and Thrichrome stain) and toxin determination ( phosphatase kit) was carried out. Alkaline phosphatase (ALP), Aspartate transaminase (AST), Alanine transaminase (ALT) were determinate on blood samples. Results and conclusions: Dose dependent cytoplasmatic microvacuolation with 35% and10% of hepatic steatosis were observed in centrolobulillar zone of mice treated with 100 μgMC-LR/kg and 50 μgMC-LR/kg respectively. However, no changes were observed in ALT, AST and FAL plasma levels. Intestine samples have shown a significant dose-dependent decrease of intraepithelial lymphocytes. These results are consistent with tissues toxin levels. These results confirm that oral exposures to low doses of MC-LR, even when go unnoticed, generate damage not only in liver but also in intestine.