Expression of cysteine aspartyl proteinase 3 from liver tissues of the porkets experimentally infected by Taenia asiatica / 中国人兽共患病学报

ABSTRACT

In order to provide substantial scientific information for exploring the mechanism of porcine liver injury caused by Taenia asiatica (T.asiatica),the expression of Cysteine aspartyl proteinase 3 (Caspase-3) from liver tissues of porkets that were experimentally infected by T.asiatica was examined.The T.asiatica adults were collected from the taeniasis patients in Duyun,Guizhou Province and identified biologically.The eggs were harvested from gravid proglottids and prepared by repeated washing and centrifugation.Twelve 20-days old Yorkshire and Seghers hybrid porkets were randomly divided into experimental and control groups as six pigs per group.The experimental group was orally administrated with 1.5 × 106 eggs per porket at day 0 post-infection.The porkets of both groups were sacrificed on the day 15 and day 75 post-infection (three pigs per time point) respectively,and liver samples were collected for further experiments.Quantitative real-time polymerase chain reaction method was employed to detect the mRNA levels of Caspase-3,and western blotting and immunohistochemistry methods were performed to detect the level of Caspase-3 expression in both groups.At the day 15 post-infection,the mRNA level and expression level of Caspase-3 of the experimental group were significantly decreased,comparison with the control group (P =0.011,P=0.008 and P=0.004 respectively).It was positive with Caspase-3 when yellow or brown signal appeared in the cytoplasm of liver cells by immunohistochemistry.However,at the day 75 post-infection,the mRNA level and expression level of Caspase-3 of the experimental group were dramatically similar to the control group.Furthermore,in the experimental group,the mRNA level and expression level of Caspase-3 were significantly increased at day 75 post-infection than day 15 post-infection (P--0.018,P=0.003 and P=0.002 respectively).These results suggested that Caspase-3 might be involved into the regulation of the damage of porcine liver induced by T.asiatica challenge at the early infection stage and have on effect to the hepatic injury because of the dramatic recovery of Caspase-3 at the consequent infection stage.