Research Article Details

Article ID: A20835
PMID: 25703085
Source: J Hepatol
Title: PPARα gene expression correlates with severity and histological treatment response in patients with non-alcoholic steatohepatitis.
Abstract: BACKGROUND & AIMS: Peroxisome proliferator-activated receptors (PPARs) have been implicated in non-alcoholic steatohepatitis (NASH) pathogenesis, mainly based on animal data. Gene expression data in NASH patients are scarce. We studied liver PPAR&#945;, &#946;/&#948;, and &#947; expression in a large cohort of obese patients assessed for presence of NAFLD at baseline and 1 year follow-up. METHODS: Patients presented to the obesity clinic underwent a hepatic work-up. If NAFLD was suspected, liver biopsy was performed. Gene expression was studied by mRNA quantification. Patients were reassessed after 1 year. RESULTS: 125 patients were consecutively included in the study, of which 85 patients had paired liver biopsy taken at 1 year of follow-up. Liver PPAR&#945; expression negatively correlated with the presence of NASH (p=0.001) and with severity of steatosis (p=0.003), ballooning (p=0.001), NASH activity score (p=0.008) and fibrosis (p=0.003). PPAR&#945; expression was positively correlated to adiponectin (R(2)=0.345, p=0.010) and inversely correlated to visceral fat (R(2)=-0.343, p<0.001), HOMA IR (R(2)=-0.411, p<0.001) and CK18 (R(2)=-0.233, p=0.012). Liver PPAR&#946;/&#948; and PPAR&#947; expression did not correlate with any histological feature nor with glucose metabolism or serum lipids. At 1 year, correlation of PPAR&#945; expression with liver histology was confirmed. In longitudinal analysis, an increase in expression of PPAR&#945; and its target genes was significantly associated with histological improvement (p=0.008). CONCLUSION: Human liver PPAR&#945; gene expression negatively correlates with NASH severity, visceral adiposity and insulin resistance and positively with adiponectin. Histological improvement is associated with an increase in expression of PPAR&#945; and its target genes. These data might suggest that PPAR&#945; is a potential therapeutic target in NASH.
DOI: 10.1016/j.jhep.2015.02.019