1
|
Brachs S, Winkel AF, Tang H, Birkenfeld AL, Brunner B, Jahn-Hofmann K, Margerie D, Ruetten H, Schmoll D, Spranger J. Inhibition of citrate cotransporter Slc13a5/mINDY by RNAi improves hepatic insulin sensitivity and prevents diet-induced non-alcoholic fatty liver disease in mice. Mol Metab 2016; 5:1072-1082. [PMID: 27818933 PMCID: PMC5081411 DOI: 10.1016/j.molmet.2016.08.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 08/02/2016] [Accepted: 08/08/2016] [Indexed: 12/22/2022] Open
Abstract
Objective Non-alcoholic fatty liver disease is a world-wide health concern and risk factor for cardio-metabolic diseases. Citrate uptake modifies intracellular hepatic energy metabolism and is controlled by the conserved sodium-dicarboxylate cotransporter solute carrier family 13 member 5 (SLC13A5, mammalian homolog of INDY: mINDY). In Drosophila melanogaster and Caenorhabditis elegans INDY reduction decreased whole-body lipid accumulation. Genetic deletion of Slc13a5 in mice protected from diet-induced adiposity and insulin resistance. We hypothesized that inducible hepatic mINDY inhibition should prevent the development of fatty liver and hepatic insulin resistance. Methods Adult C57BL/6J mice were fed a Western diet (60% kcal from fat, 21% kcal from carbohydrate) ad libitum. Knockdown of mINDY was induced by weekly injection of a chemically modified, liver-selective siRNA for 8 weeks. Mice were metabolically characterized and the effect of mINDY suppression on glucose tolerance as well as insulin sensitivity was assessed with an ipGTT and a hyperinsulinemic-euglycemic clamp. Hepatic lipid accumulation was determined by biochemical measurements and histochemistry. Results Within the 8 week intervention, hepatic mINDY expression was suppressed by a liver-selective siRNA by over 60%. mINDY knockdown improved hepatic insulin sensitivity (i.e. insulin-induced suppression of endogenous glucose production) of C57BL/6J mice in the hyperinsulinemic-euglycemic clamp. Moreover, the siRNA-mediated mINDY inhibition prevented neutral lipid storage and triglyceride accumulation in the liver, while we found no effect on body weight. Conclusions We show that inducible mINDY inhibition improved hepatic insulin sensitivity and prevented diet-induced non-alcoholic fatty liver disease in adult C57BL6/J mice. These effects did not depend on changes of body weight or body composition. mINDY/Slc13a5 knockdown was induced by liver-selective siRNA in mice. Liver-selective knockdown of mINDY improved hepatic insulin sensitivity. Liver-selective knockdown of mINDY prevented steatosis hepatis.
Collapse
Key Words
- 2-DG, 2-Deoxy-d-glucose
- Citrate transport
- EE, energy expenditure
- EGP, endogenous glucose production
- FA, fatty acids
- FLD, fatty liver disease
- GIR, glucose infusion rate
- HE clamp, hyperinsulinemic-euglycemic clamp
- HFD, high-fat diet
- IEX, anion-exchange high-performance liquid chromatography
- INDY, ‘I'm not dead Yet’
- INDY/Slc13a5
- Insulin resistance
- KO, knockout
- Lipid accumulation
- ORO, oil red O
- RER, respiratory exchange ratio
- SCR, non-silencing scrambled control siRNA
- SKM, skeletal muscle
- Steatosis
- T2D, type-2 diabetes
- TCA, tricarboxylic acid
- WAT, white adipose tissue
- WD, western diet
- e, epididymal
- mINDY, Slc13a5/SLC13A5
- p, perirenal
- s, subcutaneous
- siINDY, mINDY-specific siRNA
- siRNA
- solute carrier family 13, member 5
Collapse
Affiliation(s)
- Sebastian Brachs
- Department of Endocrinology, Diabetes and Nutrition, Center for Cardiovascular Research, Charité - University School of Medicine, Berlin, 10117, Germany; DZHK (German Center for Cardiovascular Research), Partner Site, Berlin, Germany.
| | - Angelika F Winkel
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main, 65926, Germany.
| | - Hui Tang
- Department of Endocrinology, Diabetes and Nutrition, Center for Cardiovascular Research, Charité - University School of Medicine, Berlin, 10117, Germany; DZHK (German Center for Cardiovascular Research), Partner Site, Berlin, Germany.
| | - Andreas L Birkenfeld
- Department of Endocrinology, Diabetes and Nutrition, Center for Cardiovascular Research, Charité - University School of Medicine, Berlin, 10117, Germany; DZHK (German Center for Cardiovascular Research), Partner Site, Berlin, Germany; Section of Metabolic Vascular Medicine, Medical Clinic III and Paul Langerhans Institute Dresden (PLID), a Member of the German Diabetes Center (DZD), Technische Universität, Dresden, 01307, Germany.
| | - Bodo Brunner
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main, 65926, Germany.
| | - Kerstin Jahn-Hofmann
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main, 65926, Germany.
| | - Daniel Margerie
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main, 65926, Germany.
| | - Hartmut Ruetten
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main, 65926, Germany.
| | - Dieter Schmoll
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main, 65926, Germany.
| | - Joachim Spranger
- Department of Endocrinology, Diabetes and Nutrition, Center for Cardiovascular Research, Charité - University School of Medicine, Berlin, 10117, Germany; DZHK (German Center for Cardiovascular Research), Partner Site, Berlin, Germany.
| |
Collapse
|