Serum levels of vascular endothelial growth factor in non-alcoholic fatty liver disease

BACKGROUND: This study aimed to assess the significance of serum levels of vascular endothelial growth factor (VEGF) in non-alcoholic fatty liver disease (NAFLD). METHODS: Sixty-seven consecutive NAFLD patients and 47 healthy controls who visited our liver clinics between May 2008 and December 2010 were included. The NAFLD diagnosis required elevated alanine aminotransferase and/or gamma-glutamyl transpeptidase levels, evidence of hepatic steatosis on ultrasound and/or liver histology, and exclusion of other causes of liver injury. Serum VEGF levels were determined by an enzyme immunoassay. Liver biopsy was obtained in 34 NAFLD patients. Histological lesions were scored by a liver histopathologist. RESULTS: Serum VEGF levels tended to be lower in matched NAFLD patients than in healthy controls (296±146 vs. 365±186 pg/mL, P=0.092); levels in patients with non-alcoholic steatohepatitis (NASH) also tended to be lower than in those with simple fatty liver (FL) (279±149 vs. 359±190 pg/mL, P=0.095); while VEGF levels were significantly lower in NASH patients than in healthy controls (279±149 vs. 365±186 pg/mL, P=0.041). VEGF levels offered poor predictability for the differentiation between NAFLD patients and controls or between NASH and FL patients. However, patients with high VEGF levels (≥300 pg/mL) were significantly more likely to have FL, either in the total NAFLD population (67% vs. 35%, P=0.019) or in the 34 NAFLD patients with liver biopsy (57% vs. 15%, P=0.023), while those with high VEGF levels also had a significantly lower mean fibrosis score (0.7±0.9 vs. 1.6±1.0, P=0.017). CONCLUSION: Our data suggest that serum VEGF levels are equally high in healthy controls and in patients with simple fatty liver, but tend to decrease when NASH develops.