title: The Expression of Adipogenic Genes in Adipose Tissues of Feedlot Steers Fed Supplementary Palm Oil or Soybean Oil.
abstract: We hypothesized that supplementing finishing diets with palm oil would promote adipogenic gene expression and stearoyl-CoA desaturase (SCD) gene expression in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues of feedlot steers. Eighteen Angus and Angus crossbred steers were assigned to three groups of 6 steers and fed a basal diet (control), with 3% palm oil, or with 3% soybean oil, for 70 d, top-dressed daily. Tailhead s.c. adipose tissue was obtained by biopsy at 14 d before the initiation of dietary treatments and at 35 d of dietary treatments. At slaughter, after 70 d of dietary treatment, tailhead s.c. adipose tissue and i.m. adipose tissue were obtained from the longissimus thoracis muscle. Palm oil increased plasma palmitic acid and soybean oil increased plasma linoleic acid and α-linolenic acid relative to the initial sampling time. Expression of AMP-activated protein kinase alpha (AMPKα) and peroxisome proliferator-activated receptor gamma (PPARγ) increased between the initial and intermediate biopsies and declined thereafter (p<0.03). SCD gene expression did not change between the initial and intermediate biopsies but declined by over 75% by the final period (p = 0.04), and G-coupled protein receptor 43 (GPR43) gene expression was unaffected by diet or time on trial. Soybean oil decreased (p = 0.01) PPARγ gene expression at the intermediate sample time. At the terminal sample time, PPARγ and SCD gene expression was less in i.m. adipose tissue than in s.c. adipose tissue (p<0.05). AMPKα gene expression was less in s.c. adipose tissue of palm oil-fed steers than in control steers (p = 0.04) and CCAAT enhancer binding protein-beta (CEBPβ) gene expression was less in s.c. and i.m. adipose tissues of palm oil-fed steers than in soybean oil-fed steers (p<0.03). Soybean oil decreased SCD gene expression in s.c. adipose tissue (p = 0.05); SCD gene expression in palm oil-fed steers was intermediate between control and soybean oil-fed steers. Contrary to our original hypothesis, palm oil did not promote adipogenic gene expression in s.c. and i.m. adipose tissue.
authors.affiliation: Department of Food Science and Technology, Sejong University, Seoul 143-747, Korea .
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Food Science and Technology, Sejong University, Seoul 143-747, Korea .
authors.forename: Sung Kwon
authors.initials: SK
authors.lastname: Park
authors.affiliation: Department of Animal Resources, Daegu University, Gyeongsan 712-714, Korea .
authors.forename: Chang Weon
authors.initials: CW
authors.lastname: Choi
authors.affiliation: Department of Animal Science, Yanbian University, Yanji 133002, China .
authors.forename: Xiang Zi
authors.initials: XZ
authors.lastname: Li
authors.affiliation: Graduate School of International Agricultural Technology, and Institute of Green Bio Science & Technology, Seoul National University, Seoul National University, Pyeongchang 232-916, Korea .
authors.forename: Kyoung Hoon
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Food Science and Technology, Sejong University, Seoul 143-747, Korea .
authors.forename: Won Young
authors.initials: WY
authors.lastname: Kim
authors.affiliation: Livestock Research Center, National Agricultural Cooperatives Federation, Anseong 456-824, Korea .
authors.forename: Joon
authors.initials: J
authors.lastname: Jeong
authors.affiliation: Department of Animal and Food Science, Texas Tech University, Lubbock, TX 79409, USA .
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Johnson
authors.affiliation: Department of Animal Science, Northwest Agricultural and Forestry University, Yangling 712100, China .
authors.forename: Linsen
authors.initials: L
authors.lastname: Zan
authors.affiliation: Department of Animal Science, Texas A&M University, College Station, TX 77843, USA .
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Smith
keywords: Adipose Tissue; Fatty Acids; Gene Expression; Palm Oil; Stearoyl-coenzyme A Desaturase