Serum autotaxin is independently associated with hepatic steatosis in severely obese women

OBJECTIVE: Autotaxin (ATX) is an adipocyte-derived lysophospholipase that generates the lipid signaling molecule lysophosphatidic acid (LPA). The aim of this study was to determine the relationship between serum ATX and non-alcoholic fatty liver disease (NAFLD) in obese females. DESIGN AND METHODS: 102 obese, nondiabetic women (age: 31.5-55.8 years; BMI: 35.0-64.5kg/m(2)) were classified as having NAFLD (36.3%) or not having NAFLD (63.7%) based on the degree of hepatic steatosis on abdominal CT. Subjects were characterized for metabolic phenotype including measures of energy, glucose, and lipid homeostasis. Fasting serum adipokines and inflammatory markers were determined by ELISA. Linear regression analysis was used to determine features independently associated with NAFLD. RESULTS: Subjects with and without NAFLD differed in several key features of metabolic phenotype including BMI, waist circumference, fasting glucose and insulin, HOMA-IR, VLDL, triglycerides, and ALT. Serum adipokines, including ATX and leptin, were higher in subjects with NAFLD. Serum ATX was significantly correlated with alkaline phosphatase, fasting glucose, fasting insulin, and HOMA-IR. Linear regression analysis revealed that serum triglycerides and log-transformed ATX were independently associated with hepatic steatosis. CONCLUSIONS: Serum ATX may be a potential pathogenic factor and/or biomarker for NAFLD in obese, nondiabetic women.