title: Effects of leptin, troglitazone, and dietary fat on stearoyl CoA desaturase.
abstract: Leptin, troglitazone, and high fat feeding profoundly influence the lipid content of various tissues. To determine if they affect the expression of stearoyl CoA desaturase (SCD)-1 and -2, their mRNA was measured in livers of normal, hyperleptinemic, troglitazone-treated, and fat-fed rats. Hyperleptinemia, which reduces tissue TG by downregulating lipogenic enzymes and upregulating fatty acid oxidation, lowered SCD-1 96% below controls and reduced SCD-2 slightly. By contrast, hepatic SCD-1 mRNA of leptin-resistant fa/fa rats was five times wild-type controls, but SCD-2 mRNA was 66% lower. High fat feeding lowered SCD-1 by 80%, possibly by inducing hyperleptinemia. Troglitazone treatment, which reduces nonadipose tissue TG of fa/fa rats without downregulating lipogenic enzymes, raised SCD-2 13-fold but lowered SCD-1 by 25%. The findings suggest that leptin controls SCD-1 expression and that troglitazone's antilipotoxic action may involve SCD-2 upregulation.
authors.affiliation: Department of Internal Medicine, Gifford Laboratories, Touchstone Center for Diabetes Research, University of Texas Southwestern Medical Center, Dallas, TX 75390-8854, USA.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kakuma
authors.forename: Young
authors.initials: Y
authors.lastname: Lee
authors.forename: Roger H
authors.initials: RH
authors.lastname: Unger
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002839:Chromans / Q000494:pharmacology*; D018076:DNA, Complementary / Q000378:metabolism; D004041:Dietary Fats / Q000494:pharmacology*; D015536:Down-Regulation; D005223:Fats / Q000378:metabolism; D020738:Leptin / Q000494:pharmacology*; D016014:Linear Models; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011924:Rats, Zucker; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013230:Stearoyl-CoA Desaturase / Q000737:chemistry / Q000378:metabolism*; D013844:Thiazoles / Q000494:pharmacology*; D045162:Thiazolidinediones; D000077288:Troglitazone; D015854:Up-Regulation
chemical_list: D000975:Antioxidants; D002839:Chromans; D018076:DNA, Complementary; D004041:Dietary Fats; D005223:Fats; D020738:Leptin; D012333:RNA, Messenger; D013844:Thiazoles; D045162:Thiazolidinediones; D012313:RNA; D013230:Stearoyl-CoA Desaturase; D000077288:Troglitazone