title: Inverse regulation of leptin mRNA expression by short- and long-chain fatty acids in cultured bovine adipocytes.
abstract: Leptin is an adipose tissue-derived cytokine plays key roles in the regulation of food intake and energy expenditure. However, regulatory mechanisms of leptin gene expression are not fully elucidated in ruminants that utilize short-chain fatty acids (SCFA), known as volatile fatty acids, as principal energy sources. In this study, we determined effects of SCFA and long-chain fatty acids (LCFA) on leptin expression in bovine adipocytes. Bovine stromal vascular cells isolated from subcutaneous adipose tissue of Holstein cows were cultured to confluence and treated sequentially with dexamethasone and isobutylmethylxanthine for 2 days and insulin and troglitazone for 12 days to achieve full differentiation to adipocytes. The cells started to accumulate lipids 4 days after the onset of treatment, with increased mRNA expression of leptin, as well as aP2, adiponectin, and PPAR-gamma. Removal of fetal calf serum and reduction of glucose in the culture medium of differentiated adipocytes decreased leptin mRNA expression. Subsequent addition of acetate, butyrate, or propionate dose-dependently restored and rather increased leptin expression, while addition of LCFA suppressed it. The stimulatory effect of acetate was abolished by prior treatment of the cells with pertussis toxin and by addition of LCFA. Furthermore, cows fasted for 48h and fed thereafter, elaborate reduced and increased plasma leptin levels, respectively. Thus, these results suggest that plasma leptin levels in cows are inversely controlled at the transcription level by VFA and LCFA, and that the effects of SCFA possibly act through a G protein-coupled receptor for SCFA.
authors.affiliation: Laboratory of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Soliman
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kimura
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ahmed
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamaji
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Matsushita
authors.forename: Yuko
authors.initials: Y
authors.lastname: Okamatsu-Ogura
authors.forename: Kennedy
authors.initials: K
authors.lastname: Makondo
authors.forename: Masayuki
authors.initials: M
authors.lastname: Saito
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D017667:Adipocytes / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D005215:Fasting; D005227:Fatty Acids / Q000494:pharmacology*; D005232:Fatty Acids, Volatile / Q000494:pharmacology*; D005502:Food; D019204:GTP-Binding Proteins / Q000187:drug effects / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects*; D020738:Leptin / Q000097:blood / Q000235:genetics*; D037342:Pertussis Toxin / Q000494:pharmacology; D012333:RNA, Messenger; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D005227:Fatty Acids; D005232:Fatty Acids, Volatile; D020738:Leptin; D012333:RNA, Messenger; D003907:Dexamethasone; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D015056:1-Methyl-3-isobutylxanthine