Serum transforming growth factor beta 3 predicts future development of nonalcoholic fatty liver disease

Transforming growth factor beta 3 (TGFb3) was mainly expressed by liver satellite cells in the normal liver, but it may be expressed by various liver cells during liver diseases, e.g. hepatitis and cirrhosis. However, whether TGFb3 level may be used to predict development of nonalcoholic fatty liver disease (NAFLD) has not been investigated before. Here we evaluated the relationship between TGFb3 and the susceptibility for developing NAFLD by comparing the incidence rates of developing NAFLD and serum TGFb3 levels in 1322 healthy subjects without other risk factors during a 4-year period. These healthy subjects were grouped into tertiles based on their serum TGFb3 levels that were measured in 2009. After 4 years, the odds ratios (ORs) of NAFLD development were analyzed based on the tertiles of TGFb3 levels in 2013. The cumulative incidence of NAFLD was 25.3% (334/1322) after four years. The NAFLD-developing group had higher serum TGFb3 levels in 2009 than those in the group that did not develop NAFLD (554±287 pg/ml vs. 285±173 pg/ml; P=0.002). When the serum TGFb3 levels in 2009 were grouped into tertiles, we found that the incidence of NAFLD in 2013 was significantly higher with increasing tertiles (6.3%, 38.0%, and 55.7%, respectively; P<0.05). Thus, our study demonstrate that higher serum TGFb3 levels in subjects devoid of NAFLD may have a higher chance of its future development, and highlight serum TGFb3 level as a novel predictor for development of NAFLD.