title: Effects of non-esterified fatty acids on the gluconeogenesis in bovine hepatocytes.
abstract: Dairy cows experience an increased demand for glucose to support milk production. However, negative energy balance is a common condition in peripartum cows. In response, fat mobilization provides non-esterified fatty acids (NEFAs) for oxidation in the liver to generate ATP. To investigate the effects of NEFAs on gluconeogenesis, the expression and enzyme activity of pyruvate carboxylase (PC) and phosphoenolpyruvate carboxylase (PEPCK) in cultured bovine hepatocytes were evaluated by quantitative polymerase chain reaction and spectrophotometry, respectively. The results showed that PC and PEPCK mRNA levels were marked decreased when the NEFAs concentrations exceeded 0.5 and 1.5 mmol/l, respectively. The PC and PEPCK enzyme activity showed significantly decreased when the NEFAs concentrations exceeded 1.5 and 0.5 mmol/l, respectively. These findings indicate that high circulating levels of NEFAs inhibit hepatocyte gluconeogenesis, thereby promoting negative energy balance.
authors.affiliation: College of Animal Science and Veterinary Medicine, Jilin University, 5333 Xi'an Road, Changchun, 130062, Jilin, China.
authors.forename: Xinwei
authors.initials: X
authors.lastname: Li
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Li
authors.forename: Ge
authors.initials: G
authors.lastname: Bai
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Deng
authors.forename: Zhaoxi
authors.initials: Z
authors.lastname: Liu
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.forename: Guowen
authors.initials: G
authors.lastname: Liu
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D004734:Energy Metabolism; D005230:Fatty Acids, Nonesterified / Q000097:blood* / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D005943:Gluconeogenesis / Q000187:drug effects*; D022781:Hepatocytes / Q000378:metabolism*; D008892:Milk; D010729:Phosphoenolpyruvate Carboxykinase (GTP) / Q000032:analysis / Q000235:genetics; D011766:Pyruvate Carboxylase / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D005230:Fatty Acids, Nonesterified; D012333:RNA, Messenger; D010729:Phosphoenolpyruvate Carboxykinase (GTP); D011766:Pyruvate Carboxylase