Apoliprotein A-IV as a new possible molecular ''tool'' to understand feline hepatic lipidosis physiopathology

Feline Hepatic Lipidosis (FHL) represents one of the most common metabolic disorders in cats. Apolipoprotein (apo) A-IV is a protein known to participate in the regulation of various metabolic pathways, with special regards to lipid metabolism. The present study demonstrates a relation between hepatic lipid content and apo A-IV expression in rat and cat liver, opening a fascinating innovative hypothesis on FHL pathogenesis. Livers from cats (5) and rats (8) were processed to determine hepatic lipid content using Mojonnier method. Apo A-IV liver protein expression was assessed by ELISA using liver tissue extracts. Finally, samples of all livers were processed for histopathology and immunohistochemistry to confirm previously obtained results. Data show an interesting inverse proportion between hepatic lipid content and apo A-IV liver expression, highlighting differences between cat and rat lipid metabolism. Applying this comparative experimental approach, we suggest an innovative pathogenetic hypothesis which involves apo A-IV as a ''new actor'' molecule involved in FHL determinism and its potential role as a prodromal serological diagnostic marker.