Enterotoxic effects of Aeromonas hydrophila infection in the catfish, Clarias gariepinus: Biochemical, histological and proteome analyses

In this study, the impact of A. hydrophila infection in the air-breathing catfish, Clarias gariepinus was analyzed using a multidimensional approach. Aeromonas hydrophila (1 × 107 cells) was injected into C. gariepinus intraperitoneally at an ambient temperature with periodical monitoring for morphological changes. After 7 days post-infection, tissue samples of the gills, liver, intestine, and kidney were subjected to biochemical, histological, transmission electron microscope (TEM) and proteomic analyses. Observed results indicated distinct morphological changes with the significant increase of ROS and oxidative stress enzymes (CAT and SOD) in tissues of the infected group when compared to the control. Histological analysis in infected fish revealed the presence of pyknotic nuclei, early stages of necrosis in the liver, degradation of renal tubules and presence of sinusoidal space in kidneys along with enlargement of the epithelial region in the intestine. TEM analysis of the infected intestine showed degeneration of villi and the presence of multinucleated erythrocytes. Two-dimensional proteomic and mass spectrometry analysis of intestine and liver displayed up-regulation of several immune regulatory proteins such as proteasome subunit 3 protein, prolactin and intermediated filament protein; and down-regulation of proteins including actin, serine/arginine-rich splicing factor and carbonic anhydrase. Taken together, these results suggest that the identified proteins may...
Source: Veterinary Immunology and Immunopathology - Category: Veterinary Research Source Type: research