Understanding the pathophysiology of feline hepatic lipidosis

Introduction: 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 particular importance in lipid metabolism. The present study demonstrates a relationship between hepatic lipid content and apo A-IV expression in rat and cat liver. Materials and Methods: Livers from cats (n = 5) and rats (n = 11). Hepatic lipid content was obtained using the method of Mojonnier. Apo A-IV liver protein expression was assessed by ELISA and confirmed by immunoblotting using liver tissue extracts. Finally, in attempt to graduate the degree of lipidosis histologically by comparing histological scores with the levels of apo A-IV expression, samples of all livers used in the study were processed routinely for histopathology and immunohistochemistry. Results: Preliminary results show a linear relationship between hepatic lipid content and apo A-IV liver expression, highlighting differences between cat and rat lipid metabolism. Conclusions: This comparative experimental approach has suggested a novel pathogenetic mechanism for FHL. Apo A-IV may be a ‘new’ molecule involved in FHL and has a potential role as a prodromal diagnostic biochemical marker.