The roles and interaction of FXR and PPARs in the pathogenesis of nonalcoholic fatty liver disease

To identify the roles and interaction of farnesoid X receptor (FXR) and peroxisome proliferator activated receptors (PPARs) in Non-alcoholic fatty liver disease (NAFLD) pathogenesis. 16 C57/BL male FXR knockout (KO) mice and sex- and age-matched C57/BL wild type mice were received either standard rodent chow or high-fat and sucrose diet (Blank control, NAFLD, FXR KO and FXR KO NAFLD) for 8 weeks. After that, all mice were sacrificed. Liver tissues and blood samples were collected for laboratory and RT-PCR examination. NAFLD, FXR KO and FXR KO NAFLD mouse models were successful established. Compared with blank control, FXR and PPAR-α mRNA expression decreased significantly (P < 0.05), PPAR-β expression increased slightly (P > 0.05), PPAR-γ expression increased significantly in NAFLD (P < 0.05). Slight increased PPAR-α mRNA expression (P > 0.05) and markedly decreased PPAR-β and PPAR-γ expression (P < 0.05) were found in FXR KO. Compared with FXR KO group, there was a slight increase in PPAR-αand PPAR-βmRNA expression (P > 0.05) and significant increase in PPAR-γ expression (P < 0.05) in FXR KO NAFLD group. Comparison with NAFLD, PPAR-α mRNA expression increased slightly (P > 0.05), PPAR-β and PPAR-γ expression decreased significantly (P < 0.05) in FXR KO NAFLD. FXR and PPARs interaction may play important roles in NAFLD pathogenesis.