Abstract 324: The Apolipoprotein A-IV T347S Polymorphism is Associated with Severe Hepatic Steatosis in Obese Subjects Undergoing Bariatric Surgery

Background: We recently reported that hepatic apolipoprotein A-IV (apoA-IV) gene expression is increased in mouse models of steatosis and is positively correlated with liver triglyceride (TG) content. The most common human apoA-IV polymorphism T347S (rs675) decreases its lipid affinity and is associated with increased adiposity in population studies. Hypothesis: 347S allele carriers will exhibit increased hepatic TG content in conditions predisposing to hepatic steatosis. Methods: We examined the impact of the 347S allele on liver TG content in a cohort of very obese humans. Total hepatic mRNA was extracted from snap frozen tissue obtained from 40 obese subjects (11 male, 29 female) at the time of bariatric surgery. ApoA-IV abundance was quantitated by RT-PCR; copy numbers were normalized to GAPDH. Presence of the T347S polymorphism and the next most common apoA-IV allele, S127N (rs5104), was determined by cDNA sequencing. Liver total TG was measured in solvent extracts by GLC and normalized as mg TG/g pr...