title: Restraint stress alters the duodenal expression of genes important for lipid metabolism in rat.
abstract: Stress, such as trauma and injury, is known to cause transcriptional changes in various tissues; however, there is little information on tissue-specific gene expression in response to stress. Here, we have examined duodenal gene expression in rats subjected to whole-body immobilization in order to elucidate the mechanism underlying the stress response in the duodenum--one of the tissues that is most sensitive to external stress. DNA microarray analysis revealed that the immobilization for 2 weeks caused great changes in gene expression in the rat duodenum: 165 genes exhibited more than a two-fold change in expression level (103 up-regulated; 62 down-regulated). In addition, functional classification of these genes showed that immobilization preferentially stimulated the expression of genes related to lipid metabolism, including genes encoding mitochondrial HMG-CoA synthase, a key enzyme in ketogenesis; solute carrier 27A2, a fatty acid transporter; and dienoyl CoA reductase, a key enzyme in beta-oxidation. To elucidate the factors mediating these immobilization-induced changes, we treated rats and small intestinal IEC-6 cells with dexamethasone and hydrogen peroxide. In both rats and IEC-6 cells, treatment with dexamethasone induced changes in gene expression that mimicked the immobilization-mediated increase in expression of the mitochondrial HMG-CoA synthase and dienoyl CoA reductase transcripts, suggesting that stress-induced synthesis of glucocorticoid hormones mediates, at least in part, the stress response in the duodenum. These results suggest that immobilization may alter lipid metabolism in the small intestine by modifying the expression of specific genes through which the small intestine may seek to protect itself from stress-induced damage.
authors.affiliation: Department of Clinical Nutrition, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima 770-8503, Japan. tadatoshi@nutr.med.tokushima-u.ac.jp
authors.forename: Tadatoshi
authors.initials: T
authors.lastname: Sato
authors.forename: Hironori
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Sawada
authors.forename: Kunitaka
authors.initials: K
authors.lastname: Nashiki
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Tsuji
authors.forename: Kazusa
authors.initials: K
authors.lastname: Muto
authors.forename: Hisae
authors.initials: H
authors.lastname: Kume
authors.forename: Hajime
authors.initials: H
authors.lastname: Sasaki
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Arai
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nikawa
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Taketani
authors.forename: Eiji
authors.initials: E
authors.lastname: Takeda
mesh_terms: D000818:Animals; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology; D015536:Down-Regulation; D004386:Duodenum / Q000201:enzymology / Q000378:metabolism*; D015870:Gene Expression; D006861:Hydrogen Peroxide / Q000494:pharmacology; D050356:Lipid Metabolism / Q000235:genetics*; D008297:Male; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013315:Stress, Psychological / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D003907:Dexamethasone; D006861:Hydrogen Peroxide