title: Fibroblast growth factor 21 levels are increased in nonalcoholic fatty liver disease patients and are correlated with hepatic triglyceride.
abstract: OBJECTIVE
  Fibroblast growth factor 21 (FGF21), a hormone primarily secreted by the liver in response to peroxisome proliferator-activated receptor-α (PPARα) activation, has recently been shown to possess beneficial effects on lipid metabolism and hepatic steatosis in animal models. This study investigated the association of FGF21 with nonalcoholic fatty liver disease (NAFLD) in Chinese patients.
  
  
  METHODS
  Serum FGF21 levels were determined by enzyme-linked immunosorbent assay (ELISA) in 224 NAFLD and 124 control subjects, and their association with parameters of adiposity, glucose, and lipid profiles and levels of liver injury markers was studied. Besides serum concentrations, the mRNA expression of FGF21 in the liver tissue was also quantified by real-time PCR in 17 subjects with different degrees of steatosis, and was correlated with the levels of intrahepatic lipid. The protein levels of FGF21 were determined by quantitative ELISA.
  
  
  RESULTS
  Serum FGF21 levels in patients with NAFLD (402.38 pg/ml [242.03, 618.25]) were significantly higher than those in control subjects (198.62 pg/ml [134.96, 412.62]) (p<0.01). In human liver tissues, FGF21 mRNA expression increased with the degree of steatosis. Both FGF21 mRNA expression and serum FGF21 concentrations were positively correlated with intrahepatic triglyceride (TG) having r = 0.692 and r = 0.662, respectively, at p<0.01. Furthermore, the increased expression of FGF21 was accompanied by elevated protein levels in liver tissues.
  
  
  CONCLUSIONS
  These results support the role of FGF21 as a key regulator of hepatic lipid metabolism in humans, and suggest that serum FGF21 can be potentially used as a biomarker for NAFLD.
authors.affiliation: Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Huating
authors.initials: H
authors.lastname: Li
authors.forename: Qichen
authors.initials: Q
authors.lastname: Fang
authors.forename: Fei
authors.initials: F
authors.lastname: Gao
authors.forename: Jia
authors.initials: J
authors.lastname: Fan
authors.forename: Jian
authors.initials: J
authors.lastname: Zhou
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Wang
authors.forename: Huizhen
authors.initials: H
authors.lastname: Zhang
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Pan
authors.forename: Yuqian
authors.initials: Y
authors.lastname: Bao
authors.forename: Kunsan
authors.initials: K
authors.lastname: Xiang
authors.forename: Aimin
authors.initials: A
authors.lastname: Xu
authors.forename: Weiping
authors.initials: W
authors.lastname: Jia
mesh_terms: D000328:Adult; D000368:Aged; D005234:Fatty Liver / Q000097:blood; D005260:Female; D005346:Fibroblast Growth Factors / Q000097:blood* / Q000235:genetics / Q000502:physiology; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D047493:PPAR alpha / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D014280:Triglycerides / Q000378:metabolism*; D055105:Waist Circumference; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D047493:PPAR alpha; D012333:RNA, Messenger; D014280:Triglycerides; C414620:fibroblast growth factor 21; D005346:Fibroblast Growth Factors; D005723:gamma-Glutamyltransferase